Method for transmitting broadcast signals and method for receiving broadcast signals

ABSTRACT

A method of processing supplementary content in a digital receiving apparatus, includes connecting to an external device being different from a broadcaster; receiving uncompressed audio/video (A/V) content from the external device being different from the broadcaster; extracting audio watermark from the uncompressed A/V content, wherein the audio watermark includes domain type information, time information and event flag; constructing a first uniform resource locator (URL) based on the audio watermark, transmitting a request to a remote server based on the first URL; receiving a second URL for the supplementary content from the remote server, and presenting the supplementary content based on the second URL.

CROSS-REFERENCE TO RELATED APPLICATIONS

This Application is a Continuation of U.S. patent application Ser. No.17/031,308 filed on Sep. 24, 2020, which is a Continuation of U.S.patent application Ser. No. 16/453,326 filed on Jun. 26, 2019 (now U.S.Pat. No. 10,827,232 issued on Nov. 3, 2020), which is a Continuation ofU.S. patent application Ser. No. 15/711,089 filed on Sep. 21, 2017 (nowU.S. Pat. No. 10,356,490 issued on Jul. 16, 2019), which is aContinuation of U.S. patent application Ser. No. 15/101,365 filed onJun. 2, 2016 (now U.S. Pat. No. 9,800,952 issued on Oct. 24, 2017),which is the National Phase of PCT International Application No.PCT/KR2014/011636 filed on Dec. 1, 2014, which claims the benefit under35 U.S.C. § 119(e) to U.S. Provisional Application No. 61/910,961 filedon Dec. 3, 2013, all of these applications are hereby expresslyincorporated by reference into the present application.

BACKGROUND OF THE INVENTION Field of the Invention

The present invention relates to an apparatus for transmitting broadcastsignals, an apparatus for receiving broadcast signals and methods fortransmitting and receiving broadcast signals.

Discussion of the Related Art

As analog broadcast signal transmission comes to an end, varioustechnologies for transmitting/receiving digital broadcast signals arebeing developed. A digital broadcast signal may include a larger amountof video/audio data than an analog broadcast signal and further includevarious types of additional data in addition to the video/audio data.

That is, a digital broadcast system can provide HD (high definition)images, multichannel audio and various additional services. However,data transmission efficiency for transmission of large amounts of data,robustness of transmission/reception networks and network flexibility inconsideration of mobile reception equipment need to be improved fordigital broadcast.

SUMMARY OF THE INVENTION

An object of the present invention is to provide an apparatus and methodfor transmitting broadcast signals to multiplex data of a broadcasttransmission/reception system providing two or more different broadcastservices in a time domain and transmit the multiplexed data through thesame RF signal bandwidth and an apparatus and method for receivingbroadcast signals corresponding thereto.

Another object of the present invention is to provide an apparatus fortransmitting broadcast signals, an apparatus for receiving broadcastsignals and methods for transmitting and receiving broadcast signals toclassify data corresponding to services by components, transmit datacorresponding to each component as a data pipe, receive and process thedata.

Still another object of the present invention is to provide an apparatusfor transmitting broadcast signals, an apparatus for receiving broadcastsignals and methods for transmitting and receiving broadcast signals tosignal signaling information necessary to provide broadcast signals.

To achieve the object and other advantages and in accordance with thepurpose of the invention, as embodied and broadly described herein, thepresent invention provides a method of providing interactive services.The method of providing interactive services includes receiving anuncompressed broadcast content from an external receiving unit, whereinan watermark is embedded in a frame of the uncompressed broadcastcontent; extracting the embedded watermark from the uncompressedbroadcast content; parsing the extracted watermark; generating an URL byusing information in the parsed watermark; and launching an applicationby using the generated URL, wherein the application provides theinteractive services related to the uncompressed broadcast content.

Preferably, the watermark includes an URL field including a fraction ofthe URL, an URL protocol field indicating a protocol that the URL uses.

Preferably, the generating an URL further includes: combining thefraction of the URL and protocol part of the URL indicated by the URLprotocol field, to generate the URL.

Preferably, plural watermarks are embedded in frames of the uncompressedbroadcast content, wherein each of the plural watermarks include one offractions of data, and wherein each of the plural watermarks include adelivery type field indicating that the data is divided into the pluralfractions, and being delivered by using the plural watermarks.

Preferably, sizes of the each plural watermarks for the each frames canbe adjusted by having a fraction of different sizes, based on quality ofthe each frames.

Preferably, the each plural watermarks include flag informationindicating configuration of the fraction of the data inserted in theeach plural watermarks.

Preferably, one of the watermarks includes an URL protocol fieldindicating a protocol that the URL uses, and wherein one of the otherwatermarks includes an URL field including a fraction of the URL.

Preferably, the watermark further includes a timestamp size field, atimestamp unit field, an event field and a destination type field,wherein the timestamp size field indicates number of bytes allocated fortimestamps in the watermark, wherein the timestamp unit field indicatestime unit of the timestamps, wherein the event field includes a commandrelated to the application, wherein the destination type field indicatesa secondary device that the application is targeting, and wherein thetimestamps establish time base for synchronizing the interactiveservices with the uncompressed broadcast content.

Preferably, the method further includes: delivering the information inthe parsed watermark to the secondary device that the application istargeting.

Preferably, the delivering the information further includes: processingthe information in the parsed watermark, and delivering the processedinformation to the secondary device.

In other aspect, the present invention provides an apparatus forproviding interactive services. The apparatus for providing interactiveservices includes a receiving module that receives an uncompressedbroadcast content from an external receiving unit, wherein an watermarkis embedded in a frame of the uncompressed broadcast content; anextracting module that extracts the embedded watermark from theuncompressed broadcast content; a parsing module that parses theextracted watermark; a generating module that generates an URL by usinginformation in the parsed watermark; and a launching module thatlaunches an application by using the generated URL, wherein theapplication provides the interactive services related to theuncompressed broadcast content.

Preferably, the watermark includes an URL field including a fraction ofthe URL, an URL protocol field indicating a protocol that the URL uses.

Preferably, the generating module combines the fraction of the URL andprotocol part of the URL indicated by the URL protocol field, togenerate the URL.

Preferably, plural watermarks are embedded in frames of the uncompressedbroadcast content, wherein each of the plural watermarks include one offractions of data, and wherein each of the plural watermarks include adelivery type field indicating that the data is divided into the pluralfractions, and being delivered by using the plural watermarks.

Preferably, sizes of the each plural watermarks for the each frames canbe adjusted by having a fraction of different sizes, based on quality ofthe each frames.

Preferably, the each plural watermarks include flag informationindicating configuration of the fraction of the data inserted in theeach plural watermarks.

Preferably, one of the watermarks includes an URL protocol fieldindicating a protocol that the URL uses, and wherein one of the otherwatermarks includes an URL field including a fraction of the URL.

Preferably, the watermark further includes a timestamp size field, atimestamp unit field, an event field and a destination type field,wherein the timestamp size field indicates number of bytes allocated fortimestamps in the watermark, wherein the timestamp unit field indicatestime unit of the timestamps, wherein the event field includes a commandrelated to the application, wherein the destination type field indicatesa secondary device that the application is targeting, and wherein thetimestamps establish time base for synchronizing the interactiveservices with the uncompressed broadcast content.

Preferably, the apparatus further includes: a delivering module thatdelivers the information in the parsed watermark to the secondary devicethat the application is targeting.

Preferably, the delivering module processes the information in theparsed watermark, and delivers the processed information to thesecondary device.

The present invention can process data according to servicecharacteristics to control QoS (Quality of Services) for each service orservice component, thereby providing various broadcast services.

The present invention can achieve transmission flexibility bytransmitting various broadcast services through the same RF signalbandwidth.

The present invention can improve data transmission efficiency andincrease robustness of transmission/reception of broadcast signals usinga MIMO system.

According to the present invention, it is possible to provide broadcastsignal transmission and reception methods and apparatus capable ofreceiving digital broadcast signals without error even with mobilereception equipment or in an indoor environment.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are included to provide a furtherunderstanding of the invention and are incorporated in and constitute apart of this application, illustrate embodiment(s) of the invention andtogether with the description serve to explain the principle of theinvention. In the drawings:

FIG. 1 illustrates a structure of an apparatus for transmittingbroadcast signals for future broadcast services according to anembodiment of the present invention.

FIG. 2 illustrates an input formatting block according to one embodimentof the present invention.

FIG. 3 illustrates an input formatting block according to anotherembodiment of the present invention.

FIG. 4 illustrates an input formatting block according to anotherembodiment of the present invention.

FIG. 5 illustrates a BICM block according to an embodiment of thepresent invention.

FIG. 6 illustrates a BICM block according to another embodiment of thepresent invention.

FIG. 7 illustrates a frame building block according to one embodiment ofthe present invention.

FIG. 8 illustrates an OFMD generation block according to an embodimentof the present invention.

FIG. 9 illustrates a structure of an apparatus for receiving broadcastsignals for future broadcast services according to an embodiment of thepresent invention.

FIG. 10 illustrates a frame structure according to an embodiment of thepresent invention.

FIG. 11 illustrates a signaling hierarchy structure of the frameaccording to an embodiment of the present invention.

FIG. 12 illustrates preamble signaling data according to an embodimentof the present invention.

FIG. 13 illustrates PLS1 data according to an embodiment of the presentinvention.

FIG. 14 illustrates PLS2 data according to an embodiment of the presentinvention.

FIG. 15 illustrates PLS2 data according to another embodiment of thepresent invention.

FIG. 16 illustrates a logical structure of a frame according to anembodiment of the present invention.

FIG. 17 illustrates PLS mapping according to an embodiment of thepresent invention.

FIG. 18 illustrates EAC mapping according to an embodiment of thepresent invention.

FIG. 19 illustrates FIC mapping according to an embodiment of thepresent invention.

FIG. 20 illustrates a type of DP according to an embodiment of thepresent invention.

FIG. 21 illustrates DP mapping according to an embodiment of the presentinvention.

FIG. 22 illustrates an FEC structure according to an embodiment of thepresent invention.

FIG. 23 illustrates a bit interleaving according to an embodiment of thepresent invention.

FIG. 24 illustrates a cell-word demultiplexing according to anembodiment of the present invention.

FIG. 25 illustrates a time interleaving according to an embodiment ofthe present invention.

FIG. 26 illustrates the basic operation of a twisted row-column blockinterleaver according to an embodiment of the present invention.

FIG. 27 illustrates an operation of a twisted row-column blockinterleaver according to another embodiment of the present invention.

FIG. 28 illustrates a diagonal-wise reading pattern of a twistedrow-column block interleaver according to an embodiment of the presentinvention.

FIG. 29 illustrates interleaved XFECBLOCKs from each interleaving arrayaccording to an embodiment of the present invention.

FIG. 30 is a block diagram illustrating the network topology accordingto the embodiment.

FIG. 31 is a block diagram illustrating a watermark based networktopology according to an embodiment.

FIG. 32 is a ladder diagram illustrating a data flow in a watermarkbased network topology according to an embodiment.

FIG. 33 is a view illustrating a watermark based content recognitiontiming according to an embodiment.

FIG. 34 is a block diagram illustrating a fingerprint based networktopology according to an embodiment.

FIG. 35 is a ladder diagram illustrating a data flow in a fingerprintbased network topology according to an embodiment.

FIG. 36 is a view illustrating an XML schema diagram of ACR-Resulttypecontaining a query result according to an embodiment.

FIG. 37 is a block diagram illustrating a watermark and fingerprintbased network topology according to an embodiment.

FIG. 38 is a ladder diagram illustrating a data flow in a watermark andfingerprint based network topology according to an embodiment.

FIG. 39 is a block diagram illustrating the video display deviceaccording to the embodiment.

FIG. 40 is a flowchart illustrating a method of synchronizing a playbacktime of a main AV content with a playback time of an enhanced serviceaccording to an embodiment.

FIG. 41 is a conceptual diagram illustrating a method of synchronizing aplayback time of a main AV content with a playback time of an enhancedservice according to an embodiment.

FIG. 42 is a block diagram illustrating a structure of a fingerprintbased video display device according to another embodiment.

FIG. 43 is a block diagram illustrating a structure of a watermark basedvideo display device according to another embodiment.

FIG. 44 is a diagram showing data which may be delivered via awatermarking scheme according to one embodiment of the presentinvention.

FIG. 45 is a diagram showing the meanings of the values of the timestamptype field according to one embodiment of the present invention.

FIG. 46 is a diagram showing meanings of values of a URL protocol typefield according to one embodiment of the present invention.

FIG. 47 is a flowchart illustrating a process of processing a URLprotocol type field according to one embodiment of the presentinvention.

FIG. 48 is a diagram showing the meanings of the values of an eventfield according to one embodiment of the present invention.

FIG. 49 is a diagram showing the meanings of the values of a destinationtype field according to one embodiment of the present invention.

FIG. 50 is a diagram showing the structure of data to be inserted into aWM according to embodiment #1 of the present invention.

FIG. 51 is a flowchart illustrating a process of processing a datastructure to be inserted into a WM according to embodiment #1 of thepresent invention.

FIG. 52 is a diagram showing the structure of data to be inserted into aWM according to embodiment #2 of the present invention.

FIG. 53 is a flowchart illustrating a process of processing a datastructure to be inserted into a WM according to embodiment #2 of thepresent invention.

FIG. 54 is a diagram showing the structure of data to be inserted into aWM according to embodiment #3 of the present invention.

FIG. 55 is a diagram showing the structure of data to be inserted into aWM according to embodiment #4 of the present invention.

FIG. 56 is a diagram showing the structure of data to be inserted into afirst WM according to embodiment #4 of the present invention.

FIG. 57 is a diagram showing the structure of data to be inserted into asecond WM according to embodiment #4 of the present invention.

FIG. 58 is a flowchart illustrating a process of processing thestructure of data to be inserted into a WM according to embodiment #4 ofthe present invention.

FIG. 59 is a diagram showing the structure of a watermark based imagedisplay apparatus according to another embodiment of the presentinvention.

FIG. 60 is a diagram showing a data structure according to oneembodiment of the present invention in a fingerprinting scheme.

FIG. 61 is a flowchart illustrating a process of processing a datastructure according to one embodiment of the present invention in afingerprinting scheme.

FIG. 62 illustrates a method of providing interactive services accordingto an embodiment of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

Reference will now be made in detail to the preferred embodiments of thepresent invention, examples of which are illustrated in the accompanyingdrawings. The detailed description, which will be given below withreference to the accompanying drawings, is intended to explain exemplaryembodiments of the present invention, rather than to show the onlyembodiments that can be implemented according to the present invention.The following detailed description includes specific details in order toprovide a thorough understanding of the present invention. However, itwill be apparent to those skilled in the art that the present inventionmay be practiced without such specific details.

Although most terms used in the present invention have been selectedfrom general ones widely used in the art, some terms have beenarbitrarily selected by the applicant and their meanings are explainedin detail in the following description as needed. Thus, the presentinvention should be understood based upon the intended meanings of theterms rather than their simple names or meanings.

The present invention provides apparatuses and methods for transmittingand receiving broadcast signals for future broadcast services. Futurebroadcast services according to an embodiment of the present inventioninclude a terrestrial broadcast service, a mobile broadcast service, aUHDTV service, etc. The present invention may process broadcast signalsfor the future broadcast services through non-MIMO (Multiple InputMultiple Output) or MIMO according to one embodiment. A non-MIMO schemeaccording to an embodiment of the present invention may include a MISO(Multiple Input Single Output) scheme, a SISO (Single Input SingleOutput) scheme, etc.

While MISO or MIMO uses two antennas in the following for convenience ofdescription, the present invention is applicable to systems using two ormore antennas.

The present invention may defines three physical layer (PL) profiles(base, handheld and advanced profiles), each optimized to minimizereceiver complexity while attaining the performance required for aparticular use case. The physical layer (PHY) profiles are subsets ofall configurations that a corresponding receiver should implement.

The three PHY profiles share most of the functional blocks but differslightly in specific blocks and/or parameters. Additional PHY profilescan be defined in the future. For the system evolution, future profilescan also be multiplexed with the existing profiles in a single RFchannel through a future extension frame (FEF). The details of each PHYprofile are described below.

1. Base Profile

The base profile represents a main use case for fixed receiving devicesthat are usually connected to a roof-top antenna. The base profile alsoincludes portable devices that could be transported to a place butbelong to a relatively stationary reception category. Use of the baseprofile could be extended to handheld devices or even vehicular by someimproved implementations, but those use cases are not expected for thebase profile receiver operation.

Target SNR range of reception is from approximately 10 to 20 dB, whichincludes the 15 dB SNR reception capability of the existing broadcastsystem (e.g. ATSC A/53). The receiver complexity and power consumptionis not as critical as in the battery-operated handheld devices, whichwill use the handheld profile. Key system parameters for the baseprofile are listed in below table 1.

TABLE 1 LDPC codeword length 16K, 64K bits Constellation size 4~10 bpcu(bits per channel use) Time de-interleaving memory size ≤2¹⁹ data cellsPilot patterns Pilot pattern for fixed reception FT size 16K, 32K points

2. Handheld Profile

The handheld profile is designed for use in handheld and vehiculardevices that operate with battery power. The devices can be moving withpedestrian or vehicle speed. The power consumption as well as thereceiver complexity is very important for the implementation of thedevices of the handheld profile. The target SNR range of the handheldprofile is approximately 0 to 10 dB, but can be configured to reachbelow 0 dB when intended for deeper indoor reception.

In addition to low SNR capability, resilience to the Doppler Effectcaused by receiver mobility is the most important performance attributeof the handheld profile. Key system parameters for the handheld profileare listed in the below table 2.

TABLE 2 LDPC codeword length 16K bits Constellation size 2~8 bpcu Timede-interleaving memory size ≤2¹⁸ data cells Pilot patterns Pilotpatterns for mobile and indoor reception FFT size 8K, 16K points

3. Advanced Profile

The advanced profile provides highest channel capacity at the cost ofmore implementation complexity. This profile requires using MIMOtransmission and reception, and UHDTV service is a target use case forwhich this profile is specifically designed. The increased capacity canalso be used to allow an increased number of services in a givenbandwidth, e.g., multiple SDTV or HDTV services.

The target SNR range of the advanced profile is approximately 20 to 30dB. MIMO transmission may initially use existing elliptically-polarizedtransmission equipment, with extension to full-power cross-polarizedtransmission in the future. Key system parameters for the advancedprofile are listed in below table 3.

TABLE 3 LDPC codeword length 16K, 64K bits Constellation size 8~12 bpcuTime de-interleaving memory size ≤2¹⁹ data cells Pilot patterns Pilotpattern for fixed reception FFT size 16K, 32K points

In this case, the base profile can be used as a profile for both theterrestrial broadcast service and the mobile broadcast service. That is,the base profile can be used to define a concept of a profile whichincludes the mobile profile. Also, the advanced profile can be dividedadvanced profile for a base profile with MIMO and advanced profile for ahandheld profile with MIMO. Moreover, the three profiles can be changedaccording to intention of the designer.

The following terms and definitions may apply to the present invention.The following terms and definitions can be changed according to design.

auxiliary stream: sequence of cells carrying data of as yet undefinedmodulation and coding, which may be used for future extensions or asrequired by broadcasters or network operators.

base data pipe: data pipe that carries service signaling data.

baseband frame (or BBFRAME): set of Kbch bits which form the input toone FEC encoding process (BCH and LDPC encoding).

cell: modulation value that is carried by one carrier of the OFDMtransmission.

coded block: LDPC-encoded block of PLS1 data or one of the LDPC-encodedblocks of PLS2 data.

data pipe: logical channel in the physical layer that carries servicedata or related metadata, which may carry one or multiple service(s) orservice component(s).

data pipe unit: a basic unit for allocating data cells to a DP in aframe.

data symbol: OFDM symbol in a frame which is not a preamble symbol (theframe signaling symbol and frame edge symbol is included in the datasymbol).

DP_ID: this 8-bit field identifies uniquely a DP within the systemidentified by the SYSTEM_ID.

dummy cell: cell carrying a pseudo-random value used to fill theremaining capacity not used for PLS signaling, DPs or auxiliary streams.

emergency alert channel: part of a frame that carries EAS informationdata.

frame: physical layer time slot that starts with a preamble and endswith a frame edge symbol.

frame repetition unit: a set of frames belonging to same or differentphysical layer profile including a FEF, which is repeated eight times ina super-frame.

fast information channel: a logical channel in a frame that carries themapping information between a service and the corresponding base DP.

FECBLOCK: set of LDPC-encoded bits of a DP data.

FFT size: nominal FFT size used for a particular mode, equal to theactive symbol period Ts expressed in cycles of the elementary period T.

frame signaling symbol: OFDM symbol with higher pilot density used atthe start of a frame in certain combinations of FFT size, guard intervaland scattered pilot pattern, which carries a part of the PLS data.

frame edge symbol: OFDM symbol with higher pilot density used at the endof a frame in certain combinations of FFT size, guard interval andscattered pilot pattern.

frame-group: the set of all the frames having the same PHY profile typein a super-frame.

future extension frame: physical layer time slot within the super-framethat could be used for future extension, which starts with a preamble.

Futurecast UTB system: proposed physical layer broadcasting system, ofwhich the input is one or more MPEG2-TS or IP or general stream(s) andof which the output is an RF signal.

input stream: A stream of data for an ensemble of services delivered tothe end users by the system.

normal data symbol: data symbol excluding the frame signaling symbol andthe frame edge symbol.

PHY profile: subset of all configurations that a corresponding receivershould implement.

PLS: physical layer signaling data consisting of PLS1 and PLS2.

PLS1: a first set of PLS data carried in the FSS symbols having a fixedsize, coding and modulation, which carries basic information about thesystem as well as the parameters needed to decode the PLS2.

NOTE: PLS1 data remains constant for the duration of a frame-group.

PLS2: a second set of PLS data transmitted in the FSS symbol, whichcarries more detailed PLS data about the system and the DPs.

PLS2 dynamic data: PLS2 data that may dynamically change frame-by-frame.

PLS2 static data: PLS2 data that remains static for the duration of aframe-group.

preamble signaling data: signaling data carried by the preamble symboland used to identify the basic mode of the system.

preamble symbol: fixed-length pilot symbol that carries basic PLS dataand is located in the beginning of a frame.

NOTE: The preamble symbol is mainly used for fast initial band scan todetect the system signal, its timing, frequency offset, and FFT-size.

reserved for future use: not defined by the present document but may bedefined in future.

super-frame: set of eight frame repetition units.

time interleaving block (TI block): set of cells within which timeinterleaving is carried out, corresponding to one use of the timeinterleaver memory.

TI group: unit over which dynamic capacity allocation for a particularDP is carried out, made up of an integer, dynamically varying number ofXFECBLOCKs.

NOTE: The TI group may be mapped directly to one frame or may be mappedto multiple frames. It may contain one or more TI blocks.

Type 1 DP: DP of a frame where all DPs are mapped into the frame in TDMfashion.

Type 2 DP: DP of a frame where all DPs are mapped into the frame in FDMfashion.

XFECBLOCK: set of Ncells cells carrying all the bits of one LDPCFECBLOCK.

FIG. 1 illustrates a structure of an apparatus for transmittingbroadcast signals for future broadcast services according to anembodiment of the present invention.

The apparatus for transmitting broadcast signals for future broadcastservices according to an embodiment of the present invention can includean input formatting block 1000, a BICM (Bit interleaved coding &modulation) block 1010, a frame structure block 1020, an OFDM(Orthogonal Frequency Division Multiplexing) generation block 1030 and asignaling generation block 1040. A description will be given of theoperation of each module of the apparatus for transmitting broadcastsignals.

IP stream/packets and MPEG2-TS are the main input formats, other streamtypes are handled as General Streams. In addition to these data inputs,Management Information is input to control the scheduling and allocationof the corresponding bandwidth for each input stream. One or multiple TSstream(s), IP stream(s) and/or General Stream(s) inputs aresimultaneously allowed.

The input formatting block 1000 can demultiplex each input stream intoone or multiple data pipe(s), to each of which an independent coding andmodulation is applied. The data pipe (DP) is the basic unit forrobustness control, thereby affecting quality-of-service (QoS). One ormultiple service(s) or service component(s) can be carried by a singleDP. Details of operations of the input formatting block 1000 will bedescribed later.

The data pipe is a logical channel in the physical layer that carriesservice data or related metadata, which may carry one or multipleservice(s) or service component(s).

Also, the data pipe unit: a basic unit for allocating data cells to a DPin a frame.

In the BICM block 1010, parity data is added for error correction andthe encoded bit streams are mapped to complex-value constellationsymbols. The symbols are interleaved across a specific interleavingdepth that is used for the corresponding DP. For the advanced profile,MIMO encoding is performed in the BICM block 1010 and the additionaldata path is added at the output for MIMO transmission. Details ofoperations of the BICM block 1010 will be described later.

The Frame Building block 1020 can map the data cells of the input DPsinto the OFDM symbols within a frame. After mapping, the frequencyinterleaving is used for frequency-domain diversity, especially tocombat frequency-selective fading channels. Details of operations of theFrame Building block 1020 will be described later.

After inserting a preamble at the beginning of each frame, the OFDMGeneration block 1030 can apply conventional OFDM modulation having acyclic prefix as guard interval. For antenna space diversity, adistributed MISO scheme is applied across the transmitters. In addition,a Peak-to-Average Power Reduction (PAPR) scheme is performed in the timedomain. For flexible network planning, this proposal provides a set ofvarious FFT sizes, guard interval lengths and corresponding pilotpatterns. Details of operations of the OFDM Generation block 1030 willbe described later.

The Signaling Generation block 1040 can create physical layer signalinginformation used for the operation of each functional block. Thissignaling information is also transmitted so that the services ofinterest are properly recovered at the receiver side. Details ofoperations of the Signaling Generation block 1040 will be describedlater.

FIGS. 2, 3 and 4 illustrate the input formatting block 1000 according toembodiments of the present invention. A description will be given ofeach figure.

FIG. 2 illustrates an input formatting block according to one embodimentof the present invention. FIG. 2 shows an input formatting module whenthe input signal is a single input stream.

The input formatting block illustrated in FIG. 2 corresponds to anembodiment of the input formatting block 1000 described with referenceto FIG. 1.

The input to the physical layer may be composed of one or multiple datastreams. Each data stream is carried by one DP. The mode adaptationmodules slice the incoming data stream into data fields of the basebandframe (BBF). The system supports three types of input data streams:MPEG2-TS, Internet protocol (IP) and Generic stream (GS). MPEG2-TS ischaracterized by fixed length (188 byte) packets with the first bytebeing a sync-byte (0x47). An IP stream is composed of variable length IPdatagram packets, as signaled within IP packet headers. The systemsupports both IPv4 and IPv6 for the IP stream. GS may be composed ofvariable length packets or constant length packets, signaled withinencapsulation packet headers.

(a) shows a mode adaptation block 2000 and a stream adaptation 2010 forsignal DP and (b) shows a PLS generation block 2020 and a PLS scrambler2030 for generating and processing PLS data. A description will be givenof the operation of each block.

The Input Stream Splitter splits the input TS, IP, GS streams intomultiple service or service component (audio, video, etc.) streams. Themode adaptation module 2010 is comprised of a CRC Encoder, BB (baseband)Frame Slicer, and BB Frame Header Insertion block.

The CRC Encoder provides three kinds of CRC encoding for error detectionat the user packet (UP) level, i.e., CRC-8, CRC-16, and CRC-32. Thecomputed CRC bytes are appended after the UP. CRC-8 is used for TSstream and CRC-32 for IP stream. If the GS stream doesn't provide theCRC encoding, the proposed CRC encoding should be applied.

BB Frame Slicer maps the input into an internal logical-bit format. Thefirst received bit is defined to be the MSB. The BB Frame Slicerallocates a number of input bits equal to the available data fieldcapacity. To allocate a number of input bits equal to the BBF payload,the UP packet stream is sliced to fit the data field of BBF.

BB Frame Header Insertion block can insert fixed length BBF header of 2bytes is inserted in front of the BB Frame. The BBF header is composedof STUFFI (1 bit), SYNCD (13 bits), and RFU (2 bits). In addition to thefixed 2-Byte BBF header, BBF can have an extension field (1 or 3 bytes)at the end of the 2-byte BBF header.

The stream adaptation 2010 is comprised of stuffing insertion block andBB scrambler.

The stuffing insertion block can insert stuffing field into a payload ofa BB frame. If the input data to the stream adaptation is sufficient tofill a BB-Frame, STUFFI is set to ‘0’ and the BBF has no stuffing field.Otherwise STUFFI is set to ‘1’ and the stuffing field is insertedimmediately after the BBF header. The stuffing field comprises two bytesof the stuffing field header and a variable size of stuffing data.

The BB scrambler scrambles complete BBF for energy dispersal. Thescrambling sequence is synchronous with the BBF. The scrambling sequenceis generated by the feed-back shift register.

The PLS generation block 2020 can generate physical layer signaling(PLS) data. The PLS provides the receiver with a means to accessphysical layer DPs. The PLS data consists of PLS1 data and PLS2 data.

The PLS1 data is a first set of PLS data carried in the FSS symbols inthe frame having a fixed size, coding and modulation, which carriesbasic information about the system as well as the parameters needed todecode the PLS2 data. The PLS1 data provides basic transmissionparameters including parameters required to enable the reception anddecoding of the PLS2 data. Also, the PLS1 data remains constant for theduration of a frame-group.

The PLS2 data is a second set of PLS data transmitted in the FSS symbol,which carries more detailed PLS data about the system and the DPs. ThePLS2 contains parameters that provide sufficient information for thereceiver to decode the desired DP. The PLS2 signaling further consistsof two types of parameters, PLS2 Static data (PLS2-STAT data) and PLS2dynamic data (PLS2-DYN data). The PLS2 Static data is PLS2 data thatremains static for the duration of a frame-group and the PLS2 dynamicdata is PLS2 data that may dynamically change frame-by-frame.

Details of the PLS data will be described later.

The PLS scrambler 2030 can scramble the generated PLS data for energydispersal.

The above-described blocks may be omitted or replaced by blocks havingsimilar or identical functions.

FIG. 3 illustrates an input formatting block according to anotherembodiment of the present invention.

The input formatting block illustrated in FIG. 3 corresponds to anembodiment of the input formatting block 1000 described with referenceto FIG. 1.

FIG. 3 shows a mode adaptation block of the input formatting block whenthe input signal corresponds to multiple input streams.

The mode adaptation block of the input formatting block for processingthe multiple input streams can independently process the multiple inputstreams.

Referring to FIG. 3, the mode adaptation block for respectivelyprocessing the multiple input streams can include an input streamsplitter 3000, an input stream synchronizer 3010, a compensating delayblock 3020, a null packet deletion block 3030, a head compression block3040, a CRC encoder 3050, a BB frame slicer 3060 and a BB headerinsertion block 3070. Description will be given of each block of themode adaptation block.

Operations of the CRC encoder 3050, BB frame slicer 3060 and BB headerinsertion block 3070 correspond to those of the CRC encoder, BB frameslicer and BB header insertion block described with reference to FIG. 2and thus description thereof is omitted.

The input stream splitter 3000 can split the input TS, IP, GS streamsinto multiple service or service component (audio, video, etc.) streams.

The input stream synchronizer 3010 may be referred as ISSY. The ISSY canprovide suitable means to guarantee Constant Bit Rate (CBR) and constantend-to-end transmission delay for any input data format. The ISSY isalways used for the case of multiple DPs carrying TS, and optionallyused for multiple DPs carrying GS streams.

The compensating delay block 3020 can delay the split TS packet streamfollowing the insertion of ISSY information to allow a TS packetrecombining mechanism without requiring additional memory in thereceiver.

The null packet deletion block 3030, is used only for the TS inputstream case. Some TS input streams or split TS streams may have a largenumber of null-packets present in order to accommodate VBR (variablebit-rate) services in a CBR TS stream. In this case, in order to avoidunnecessary transmission overhead, null-packets can be identified andnot transmitted. In the receiver, removed null-packets can bere-inserted in the exact place where they were originally by referenceto a deleted null-packet (DNP) counter that is inserted in thetransmission, thus guaranteeing constant bit-rate and avoiding the needfor time-stamp (PCR) updating.

The head compression block 3040 can provide packet header compression toincrease transmission efficiency for TS or IP input streams. Because thereceiver can have a priori information on certain parts of the header,this known information can be deleted in the transmitter.

For Transport Stream, the receiver has a-priori information about thesync-byte configuration (0x47) and the packet length (188 Byte). If theinput TS stream carries content that has only one PID, i.e., for onlyone service component (video, audio, etc.) or service sub-component (SVCbase layer, SVC enhancement layer, MVC base view or MVC dependentviews), TS packet header compression can be applied (optionally) to theTransport Stream. IP packet header compression is used optionally if theinput steam is an IP stream.

The above-described blocks may be omitted or replaced by blocks havingsimilar or identical functions.

FIG. 4 illustrates an input formatting block according to anotherembodiment of the present invention.

The input formatting block illustrated in FIG. 4 corresponds to anembodiment of the input formatting block 1000 described with referenceto FIG. 1.

FIG. 4 illustrates a stream adaptation block of the input formattingmodule when the input signal corresponds to multiple input streams.

Referring to FIG. 4, the mode adaptation block for respectivelyprocessing the multiple input streams can include a scheduler 4000, an1-Frame delay block 4010, a stuffing insertion block 4020, an in-bandsignaling 4030, a BB Frame scrambler 4040, a PLS generation block 4050and a PLS scrambler 4060. Description will be given of each block of thestream adaptation block.

Operations of the stuffing insertion block 4020, the BB Frame scrambler4040, the PLS generation block 4050 and the PLS scrambler 4060correspond to those of the stuffing insertion block, BB scrambler, PLSgeneration block and the PLS scrambler described with reference to FIG.2 and thus description thereof is omitted.

The scheduler 4000 can determine the overall cell allocation across theentire frame from the amount of FECBLOCKs of each DP. Including theallocation for PLS, EAC and FIC, the scheduler generate the values ofPLS2-DYN data, which is transmitted as in-band signaling or PLS cell inFSS of the frame. Details of FECBLOCK, EAC and FIC will be describedlater.

The 1-Frame delay block 4010 can delay the input data by onetransmission frame such that scheduling information about the next framecan be transmitted through the current frame for in-band signalinginformation to be inserted into the DPs.

The in-band signaling 4030 can insert un-delayed part of the PLS2 datainto a DP of a frame.

The above-described blocks may be omitted or replaced by blocks havingsimilar or identical functions.

FIG. 5 illustrates a BICM block according to an embodiment of thepresent invention.

The BICM block illustrated in FIG. 5 corresponds to an embodiment of theBICM block 1010 described with reference to FIG. 1.

As described above, the apparatus for transmitting broadcast signals forfuture broadcast services according to an embodiment of the presentinvention can provide a terrestrial broadcast service, mobile broadcastservice, UHDTV service, etc.

Since QoS (quality of service) depends on characteristics of a serviceprovided by the apparatus for transmitting broadcast signals for futurebroadcast services according to an embodiment of the present invention,data corresponding to respective services needs to be processed throughdifferent schemes. Accordingly, the a BICM block according to anembodiment of the present invention can independently process DPs inputthereto by independently applying SISO, MISO and MIMO schemes to thedata pipes respectively corresponding to data paths. Consequently, theapparatus for transmitting broadcast signals for future broadcastservices according to an embodiment of the present invention can controlQoS for each service or service component transmitted through each DP.

(a) shows the BICM block shared by the base profile and the handheldprofile and (b) shows the BICM block of the advanced profile.

The BICM block shared by the base profile and the handheld profile andthe BICM block of the advanced profile can include plural processingblocks for processing each DP.

A description will be given of each processing block of the BICM blockfor the base profile and the handheld profile and the BICM block for theadvanced profile.

A processing block 5000 of the BICM block for the base profile and thehandheld profile can include a Data FEC encoder 5010, a bit interleaver5020, a constellation mapper 5030, an SSD (Signal Space Diversity)encoding block 5040 and a time interleaver 5050.

The Data FEC encoder 5010 can perform the FEC encoding on the input BBFto generate FECBLOCK procedure using outer coding (BCH), and innercoding (LDPC). The outer coding (BCH) is optional coding method. Detailsof operations of the Data FEC encoder 5010 will be described later.

The bit interleaver 5020 can interleave outputs of the Data FEC encoder5010 to achieve optimized performance with combination of the LDPC codesand modulation scheme while providing an efficiently implementablestructure. Details of operations of the bit interleaver 5020 will bedescribed later.

The constellation mapper 5030 can modulate each cell word from the bitinterleaver 5020 in the base and the handheld profiles, or cell wordfrom the Cell-word demultiplexer 5010-1 in the advanced profile usingeither QPSK, QAM-16, non-uniform QAM (NUQ-64, NUQ-256, NUQ-1024) ornon-uniform constellation (NUC-16, NUC-64, NUC-256, NUC-1024) to give apower-normalized constellation point, el. This constellation mapping isapplied only for DPs. Observe that QAM-16 and NUQs are square shaped,while NUCs have arbitrary shape. When each constellation is rotated byany multiple of 90 degrees, the rotated constellation exactly overlapswith its original one. This “rotation-sense” symmetric property makesthe capacities and the average powers of the real and imaginarycomponents equal to each other. Both NUQs and NUCs are definedspecifically for each code rate and the particular one used is signaledby the parameter DP_MOD filed in PLS2 data.

The SSD encoding block 5040 can precode cells in two (2D), three (3D),and four (4D) dimensions to increase the reception robustness underdifficult fading conditions.

The time interleaver 5050 can operates at the DP level. The parametersof time interleaving (TI) may be set differently for each DP. Details ofoperations of the time interleaver 5050 will be described later.

A processing block 5000-1 of the BICM block for the advanced profile caninclude the Data FEC encoder, bit interleaver, constellation mapper, andtime interleaver. However, the processing block 5000-1 is distinguishedfrom the processing block 5000 further includes a cell-worddemultiplexer 5010-1 and a MIMO encoding block 5020-1.

Also, the operations of the Data FEC encoder, bit interleaver,constellation mapper, and time interleaver in the processing block5000-1 correspond to those of the Data FEC encoder 5010, bit interleaver5020, constellation mapper 5030, and time interleaver 5050 described andthus description thereof is omitted.

The cell-word demultiplexer 5010-1 is used for the DP of the advancedprofile to divide the single cell-word stream into dual cell-wordstreams for MIMO processing. Details of operations of the cell-worddemultiplexer 5010-1 will be described later.

The MIMO encoding block 5020-1 can processing the output of thecell-word demultiplexer 5010-1 using MIMO encoding scheme. The MIMOencoding scheme was optimized for broadcasting signal transmission. TheMIMO technology is a promising way to get a capacity increase but itdepends on channel characteristics. Especially for broadcasting, thestrong LOS component of the channel or a difference in the receivedsignal power between two antennas caused by different signal propagationcharacteristics makes it difficult to get capacity gain from MIMO. Theproposed MIMO encoding scheme overcomes this problem using arotation-based pre-coding and phase randomization of one of the MIMOoutput signals.

MIMO encoding is intended for a 2×2 MIMO system requiring at least twoantennas at both the transmitter and the receiver. Two MIMO encodingmodes are defined in this proposal; full-rate spatial multiplexing(FR-SM) and full-rate full-diversity spatial multiplexing (FRFD-SM). TheFR-SM encoding provides capacity increase with relatively smallcomplexity increase at the receiver side while the FRFD-SM encodingprovides capacity increase and additional diversity gain with a greatcomplexity increase at the receiver side. The proposed MIMO encodingscheme has no restriction on the antenna polarity configuration.

MIMO processing is required for the advanced profile frame, which meansall DPs in the advanced profile frame are processed by the MIMO encoder.MIMO processing is applied at DP level. Pairs of the ConstellationMapper outputs NUQ (e1,i and e2,i) are fed to the input of the MIMOEncoder. Paired MIMO Encoder output (g1,i and g2,i) is transmitted bythe same carrier k and OFDM symbol 1 of their respective TX antennas.

The above-described blocks may be omitted or replaced by blocks havingsimilar or identical functions.

FIG. 6 illustrates a BICM block according to another embodiment of thepresent invention.

The BICM block illustrated in FIG. 6 corresponds to an embodiment of theBICM block 1010 described with reference to FIG. 1.

FIG. 6 illustrates a BICM block for protection of physical layersignaling (PLS), emergency alert channel (EAC) and fast informationchannel (FIC). EAC is a part of a frame that carries EAS informationdata and FIC is a logical channel in a frame that carries the mappinginformation between a service and the corresponding base DP. Details ofthe EAC and FIC will be described later.

Referring to FIG. 6, the BICM block for protection of PLS, EAC and FICcan include a PLS FEC encoder 6000, a bit interleaver 6010, and aconstellation mapper 6020.

Also, the PLS FEC encoder 6000 can include a scrambler, BCHencoding/zero insertion block, LDPC encoding block and LDPC paritypuncturing block. Description will be given of each block of the BICMblock.

The PLS FEC encoder 6000 can encode the scrambled PLS 1/2 data, EAC andFIC section.

The scrambler can scramble PLS1 data and PLS2 data before BCH encodingand shortened and punctured LDPC encoding.

The BCH encoding/zero insertion block can perform outer encoding on thescrambled PLS 1/2 data using the shortened BCH code for PLS protectionand insert zero bits after the BCH encoding. For PLS1 data only, theoutput bits of the zero insertion may be permuted before LDPC encoding.

The LDPC encoding block can encode the output of the BCH encoding/zeroinsertion block using LDPC code. To generate a complete coded block,Cldpc, parity bits, Pldpc are encoded systematically from eachzero-inserted PLS information block, Ildpc and appended after it.

$\begin{matrix}{C_{ldpc} = {\left\lbrack {I_{ldpc}\mspace{14mu} P_{ldpc}} \right\rbrack = \left\lbrack {i_{0},i_{1},\ldots\;,i_{K_{ldpc} - 1},p_{0},p_{1},\ldots\;,p_{N_{ldpc} - K_{ldpc} - 1}} \right\rbrack}} & \left\lbrack {{Math}\mspace{14mu}{Figure}\mspace{14mu} 1} \right\rbrack\end{matrix}$

The LDPC code parameters for PLS1 and PLS2 are as following table 4.

TABLE 4 Signaling K_(ldpc) code Type K_(sig) K_(bch) N_(bch)_parity(=N_(bch)) N_(ldpc) N_(ldpc)_parity rate Q_(ldpc) PLS1    342 1020 601080 4320 3240 1/4  36 PLS2 <1021 >1020 2100 2160 7200 5040 3/10 56

The LDPC parity puncturing block can perform puncturing on the PLS1 dataand PLS 2 data.

When shortening is applied to the PLS1 data protection, some LDPC paritybits are punctured after LDPC encoding. Also, for the PLS2 dataprotection, the LDPC parity bits of PLS2 are punctured after LDPCencoding. These punctured bits are not transmitted.

The bit interleaver 6010 can interleave the each shortened and puncturedPLS1 data and PLS2 data.

The constellation mapper 6020 can map the bit interleaved PLS1 data andPLS2 data onto constellations.

The above-described blocks may be omitted or replaced by blocks havingsimilar or identical functions.

FIG. 7 illustrates a frame building block according to one embodiment ofthe present invention.

The frame building block illustrated in FIG. 7 corresponds to anembodiment of the frame building block 1020 described with reference toFIG. 1.

Referring to FIG. 7, the frame building block can include a delaycompensation block 7000, a cell mapper 7010 and a frequency interleaver7020. Description will be given of each block of the frame buildingblock.

The delay compensation block 7000 can adjust the timing between the datapipes and the corresponding PLS data to ensure that they are co-timed atthe transmitter end. The PLS data is delayed by the same amount as datapipes are by addressing the delays of data pipes caused by the InputFormatting block and BICM block. The delay of the BICM block is mainlydue to the time interleaver. In-band signaling data carries informationof the next TI group so that they are carried one frame ahead of the DPsto be signaled. The Delay Compensating block delays in-band signalingdata accordingly.

The cell mapper 7010 can map PLS, EAC, FIC, DPs, auxiliary streams anddummy cells into the active carriers of the OFDM symbols in the frame.The basic function of the cell mapper 7010 is to map data cells producedby the TIs for each of the DPs, PLS cells, and EAC/FIC cells, if any,into arrays of active OFDM cells corresponding to each of the OFDMsymbols within a frame. Service signaling data (such as PSI(programspecific information)/SI) can be separately gathered and sent by a datapipe. The Cell Mapper operates according to the dynamic informationproduced by the scheduler and the configuration of the frame structure.Details of the frame will be described later.

The frequency interleaver 7020 can randomly interleave data cellsreceived from the cell mapper 7010 to provide frequency diversity. Also,the frequency interleaver 7020 can operate on very OFDM symbol paircomprised of two sequential OFDM symbols using a differentinterleaving-seed order to get maximum interleaving gain in a singleframe.

The above-described blocks may be omitted or replaced by blocks havingsimilar or identical functions.

FIG. 8 illustrates an OFMD generation block according to an embodimentof the present invention.

The OFMD generation block illustrated in FIG. 8 corresponds to anembodiment of the OFMD generation block 1030 described with reference toFIG. 1.

The OFDM generation block modulates the OFDM carriers by the cellsproduced by the Frame Building block, inserts the pilots, and producesthe time domain signal for transmission. Also, this block subsequentlyinserts guard intervals, and applies PAPR (Peak-to-Average Power Radio)reduction processing to produce the final RF signal.

Referring to FIG. 8, the frame building block can include a pilot andreserved tone insertion block 8000, a 2D-eSFN encoding block 8010, anIFFT (Inverse Fast Fourier Transform) block 8020, a PAPR reduction block8030, a guard interval insertion block 8040, a preamble insertion block8050, other system insertion block 8060 and a DAC block 8070.Description will be given of each block of the frame building block.

The pilot and reserved tone insertion block 8000 can insert pilots andthe reserved tone.

Various cells within the OFDM symbol are modulated with referenceinformation, known as pilots, which have transmitted values known apriori in the receiver. The information of pilot cells is made up ofscattered pilots, continual pilots, edge pilots, FSS (frame signalingsymbol) pilots and FES (frame edge symbol) pilots. Each pilot istransmitted at a particular boosted power level according to pilot typeand pilot pattern. The value of the pilot information is derived from areference sequence, which is a series of values, one for eachtransmitted carrier on any given symbol. The pilots can be used forframe synchronization, frequency synchronization, time synchronization,channel estimation, and transmission mode identification, and also canbe used to follow the phase noise.

Reference information, taken from the reference sequence, is transmittedin scattered pilot cells in every symbol except the preamble, FSS andFES of the frame. Continual pilots are inserted in every symbol of theframe. The number and location of continual pilots depends on both theFFT size and the scattered pilot pattern. The edge carriers are edgepilots in every symbol except for the preamble symbol. They are insertedin order to allow frequency interpolation up to the edge of thespectrum. FSS pilots are inserted in FSS(s) and FES pilots are insertedin FES. They are inserted in order to allow time interpolation up to theedge of the frame.

The system according to an embodiment of the present invention supportsthe SFN network, where distributed MISO scheme is optionally used tosupport very robust transmission mode. The 2D-eSFN is a distributed MISOscheme that uses multiple TX antennas, each of which is located in thedifferent transmitter site in the SFN network.

The 2D-eSFN encoding block 8010 can process a 2D-eSFN processing todistorts the phase of the signals transmitted from multipletransmitters, in order to create both time and frequency diversity inthe SFN configuration. Hence, burst errors due to low flat fading ordeep-fading for a long time can be mitigated.

The IFFT block 8020 can modulate the output from the 2D-eSFN encodingblock 8010 using OFDM modulation scheme. Any cell in the data symbolswhich has not been designated as a pilot (or as a reserved tone) carriesone of the data cells from the frequency interleaver. The cells aremapped to OFDM carriers.

The PAPR reduction block 8030 can perform a PAPR reduction on inputsignal using various PAPR reduction algorithm in the time domain.

The guard interval insertion block 8040 can insert guard intervals andthe preamble insertion block 8050 can insert preamble in front of thesignal. Details of a structure of the preamble will be described later.The other system insertion block 8060 can multiplex signals of aplurality of broadcast transmission/reception systems in the time domainsuch that data of two or more different broadcast transmission/receptionsystems providing broadcast services can be simultaneously transmittedin the same RF signal bandwidth. In this case, the two or more differentbroadcast transmission/reception systems refer to systems providingdifferent broadcast services. The different broadcast services may referto a terrestrial broadcast service, mobile broadcast service, etc. Datarelated to respective broadcast services can be transmitted throughdifferent frames.

The DAC block 8070 can convert an input digital signal into an analogsignal and output the analog signal. The signal output from the DACblock 7800 can be transmitted through multiple output antennas accordingto the physical layer profiles. A Tx antenna according to an embodimentof the present invention can have vertical or horizontal polarity.

The above-described blocks may be omitted or replaced by blocks havingsimilar or identical functions according to design.

FIG. 9 illustrates a structure of an apparatus for receiving broadcastsignals for future broadcast services according to an embodiment of thepresent invention.

The apparatus for receiving broadcast signals for future broadcastservices according to an embodiment of the present invention cancorrespond to the apparatus for transmitting broadcast signals forfuture broadcast services, described with reference to FIG. 1.

The apparatus for receiving broadcast signals for future broadcastservices according to an embodiment of the present invention can includea synchronization & demodulation module 9000, a frame parsing module9010, a demapping & decoding module 9020, an output processor 9030 and asignaling decoding module 9040. A description will be given of operationof each module of the apparatus for receiving broadcast signals.

The synchronization & demodulation module 9000 can receive input signalsthrough m Rx antennas, perform signal detection and synchronization withrespect to a system corresponding to the apparatus for receivingbroadcast signals and carry out demodulation corresponding to a reverseprocedure of the procedure performed by the apparatus for transmittingbroadcast signals.

The frame parsing module 9100 can parse input signal frames and extractdata through which a service selected by a user is transmitted. If theapparatus for transmitting broadcast signals performs interleaving, theframe parsing module 9100 can carry out deinterleaving corresponding toa reverse procedure of interleaving. In this case, the positions of asignal and data that need to be extracted can be obtained by decodingdata output from the signaling decoding module 9400 to restorescheduling information generated by the apparatus for transmittingbroadcast signals.

The demapping & decoding module 9200 can convert the input signals intobit domain data and then deinterleave the same as necessary. Thedemapping & decoding module 9200 can perform demapping for mappingapplied for transmission efficiency and correct an error generated on atransmission channel through decoding. In this case, the demapping &decoding module 9200 can obtain transmission parameters necessary fordemapping and decoding by decoding the data output from the signalingdecoding module 9400.

The output processor 9300 can perform reverse procedures of variouscompression/signal processing procedures which are applied by theapparatus for transmitting broadcast signals to improve transmissionefficiency. In this case, the output processor 9300 can acquirenecessary control information from data output from the signalingdecoding module 9400. The output of the output processor 8300corresponds to a signal input to the apparatus for transmittingbroadcast signals and may be MPEG-TSs, IP streams (IPv4 or IPv6) andgeneric streams.

The signaling decoding module 9400 can obtain PLS information from thesignal demodulated by the synchronization & demodulation module 9000. Asdescribed above, the frame parsing module 9100, demapping & decodingmodule 9200 and output processor 9300 can execute functions thereofusing the data output from the signaling decoding module 9400.

FIG. 10 illustrates a frame structure according to an embodiment of thepresent invention.

FIG. 10 shows an example configuration of the frame types and FRUs in asuper-frame. (a) shows a super frame according to an embodiment of thepresent invention, (b) shows FRU (Frame Repetition Unit) according to anembodiment of the present invention, (c) shows frames of variable PHYprofiles in the FRU and (d) shows a structure of a frame.

A super-frame may be composed of eight FRUs. The FRU is a basicmultiplexing unit for TDM of the frames, and is repeated eight times ina super-frame.

Each frame in the FRU belongs to one of the PHY profiles, (base,handheld, advanced) or FEF. The maximum allowed number of the frames inthe FRU is four and a given PHY profile can appear any number of timesfrom zero times to four times in the FRU (e.g., base, base, handheld,advanced). PHY profile definitions can be extended using reserved valuesof the PHY_PROFILE in the preamble, if required.

The FEF part is inserted at the end of the FRU, if included. When theFEF is included in the FRU, the minimum number of FEFs is 8 in asuper-frame. It is not recommended that FEF parts be adjacent to eachother.

One frame is further divided into a number of OFDM symbols and apreamble. As shown in (d), the frame comprises a preamble, one or moreframe signaling symbols (FSS), normal data symbols and a frame edgesymbol (FES).

The preamble is a special symbol that enables fast Futurecast UTB systemsignal detection and provides a set of basic transmission parameters forefficient transmission and reception of the signal. The detaileddescription of the preamble will be will be described later.

The main purpose of the FSS(s) is to carry the PLS data. For fastsynchronization and channel estimation, and hence fast decoding of PLSdata, the FSS has more dense pilot pattern than the normal data symbol.The FES has exactly the same pilots as the FSS, which enablesfrequency-only interpolation within the FES and temporal interpolation,without extrapolation, for symbols immediately preceding the FES.

FIG. 11 illustrates a signaling hierarchy structure of the frameaccording to an embodiment of the present invention.

FIG. 11 illustrates the signaling hierarchy structure, which is splitinto three main parts: the preamble signaling data 11000, the PLS1 data11010 and the PLS2 data 11020. The purpose of the preamble, which iscarried by the preamble symbol in every frame, is to indicate thetransmission type and basic transmission parameters of that frame. ThePLS1 enables the receiver to access and decode the PLS2 data, whichcontains the parameters to access the DP of interest. The PLS2 iscarried in every frame and split into two main parts: PLS2-STAT data andPLS2-DYN data. The static and dynamic portion of PLS2 data is followedby padding, if necessary.

FIG. 12 illustrates preamble signaling data according to an embodimentof the present invention.

Preamble signaling data carries 21 bits of information that are neededto enable the receiver to access PLS data and trace DPs within the framestructure. Details of the preamble signaling data are as follows:

PHY_PROFILE: This 3-bit field indicates the PHY profile type of thecurrent frame. The mapping of different PHY profile types is given inbelow table 5.

TABLE 5 Value PHY profile 000 Base profile 001 Handheld profile 010Advanced profiled 011~110 Reserved 111 FEF

FFT_SIZE: This 2 bit field indicates the FFT size of the current framewithin a frame-group, as described in below table 6.

TABLE 6 Value FFT size 00  8K FFT 01 16K FFT 10 32K FFT 11 Reserved

GI_FRACTION: This 3 bit field indicates the guard interval fractionvalue in the current super-frame, as described in below table 7.

TABLE 7 Value GI_FRACTION 000 1/5  001 1/10  010 1/20  011 1/40  1001/80  101 1/160 110~111 Reserved

EAC_FLAG: This 1 bit field indicates whether the EAC is provided in thecurrent frame. If this field is set to ‘1’, emergency alert service(EAS) is provided in the current frame. If this field set to ‘0’, EAS isnot carried in the current frame. This field can be switched dynamicallywithin a super-frame.

PILOT_MODE: This 1-bit field indicates whether the pilot mode is mobilemode or fixed mode for the current frame in the current frame-group. Ifthis field is set to ‘0’, mobile pilot mode is used. If the field is setto ‘1’, the fixed pilot mode is used.

PAPR_FLAG: This 1-bit field indicates whether PAPR reduction is used forthe current frame in the current frame-group. If this field is set tovalue ‘1’, tone reservation is used for PAPR reduction. If this field isset to ‘0’, PAPR reduction is not used.

FRU_CONFIGURE: This 3-bit field indicates the PHY profile typeconfigurations of the frame repetition units (FRU) that are present inthe current super-frame. All profile types conveyed in the currentsuper-frame are identified in this field in all preambles in the currentsuper-frame. The 3-bit field has a different definition for eachprofile, as show in below table 8.

TABLE 8 Current Current Current PHY_PROFILE PHY_PROFILE CurrentPHY_PROFILE = ‘001’ = ‘010’ PHY_PROFILE = ‘000’ (base) (handheld)(advanced) = ‘111’ (FEF) FRU_CONFIGURE Only base Only handheld Onlyadvanced Only FEF = 000 profile profile present profile present presentpresent FRU_CONFIGURE Handheld profile Base profile Base profile Baseprofile = 1XX present present present present FRU_CONFIGURE AdvancedAdvanced Handheld profile Handheld profile = X1X profile profile presentpresent present present FRU_CONFIGURE FEF FEF FEF Advanced = XX1 presentpresent present profile present

RESERVED: This 7-bit field is reserved for future use.

FIG. 13 illustrates PLS1 data according to an embodiment of the presentinvention.

PLS1 data provides basic transmission parameters including parametersrequired to enable the reception and decoding of the PLS2. As abovementioned, the PLS1 data remain unchanged for the entire duration of oneframe-group. The detailed definition of the signaling fields of the PLS1data are as follows:

PREAMBLE_DATA: This 20-bit field is a copy of the preamble signalingdata excluding the EAC_FLAG.

NUM_FRAME_FRU: This 2-bit field indicates the number of the frames perFRU.

PAYLOAD_TYPE: This 3-bit field indicates the format of the payload datacarried in the frame-group. PAYLOAD_TYPE is signaled as shown in table9.

TABLE 9 value Payload type 1XX TS stream is transmitted X1X IP stream istransmitted XX1 GS stream is transmitted

NUM_FSS: This 2-bit field indicates the number of FSS symbols in thecurrent frame.

SYSTEM_VERSION: This 8-bit field indicates the version of thetransmitted signal format. The SYSTEM_VERSION is divided into two 4-bitfields, which are a major version and a minor version.

Major version: The MSB four bits of SYSTEM_VERSION field indicate majorversion information. A change in the major version field indicates anon-backward-compatible change. The default value is ‘0000’. For theversion described in this standard, the value is set to ‘0000’.

Minor version: The LSB four bits of SYSTEM_VERSION field indicate minorversion information. A change in the minor version field isbackward-compatible.

CELL_ID: This is a 16-bit field which uniquely identifies a geographiccell in an ATSC network. An ATSC cell coverage area may consist of oneor more frequencies, depending on the number of frequencies used perFuturecast UTB system. If the value of the CELL_ID is not known orunspecified, this field is set to ‘0’.

NETWORK_ID: This is a 16-bit field which uniquely identifies the currentATSC network.

SYSTEM_ID: This 16-bit field uniquely identifies the Futurecast UTBsystem within the ATSC network. The Futurecast UTB system is theterrestrial broadcast system whose input is one or more input streams(TS, IP, GS) and whose output is an RF signal. The Futurecast UTB systemcarries one or more PHY profiles and FEF, if any. The same FuturecastUTB system may carry different input streams and use different RFfrequencies in different geographical areas, allowing local serviceinsertion. The frame structure and scheduling is controlled in one placeand is identical for all transmissions within a Futurecast UTB system.One or more Futurecast UTB systems may have the same SYSTEM_ID meaningthat they all have the same physical layer structure and configuration.

The following loop consists of FRU_PHY_PROFILE, FRU_FRAME_LENGTH,FRU_GI_FRACTION, and RESERVED which are used to indicate the FRUconfiguration and the length of each frame type. The loop size is fixedso that four PHY profiles (including a FEF) are signaled within the FRU.If NUM_FRAME_FRU is less than 4, the unused fields are filled withzeros.

FRU_PHY_PROFILE: This 3-bit field indicates the PHY profile type of the(i+1)th (i is the loop index) frame of the associated FRU. This fielduses the same signaling format as shown in the table 8.

FRU_FRAME_LENGTH: This 2-bit field indicates the length of the (i+1)thframe of the associated FRU. Using FRU_FRAME_LENGTH together withFRU_GI_FRACTION, the exact value of the frame duration can be obtained.

FRU_GI_FRACTION: This 3-bit field indicates the guard interval fractionvalue of the (i+1)th frame of the associated FRU. FRU_GI_FRACTION issignaled according to the table 7.

RESERVED: This 4-bit field is reserved for future use.

The following fields provide parameters for decoding the PLS2 data.

PLS2_FEC_TYPE: This 2-bit field indicates the FEC type used by the PLS2protection. The FEC type is signaled according to table 10. The detailsof the LDPC codes will be described later.

TABLE 10 Content PLS2 FEC type 00 4K-1/4 and 7K-3/10 LDPC codes 01~11Reserved

PLS2_MOD: This 3-bit field indicates the modulation type used by thePLS2. The modulation type is signaled according to table 11.

TABLE 11 Value PLS2_MODE 000 BPSK 001 QPSK 010 QAM-16 011 NUQ-64 100~111Reserved

PLS2_SIZE_CELL: This 15-bit field indicates Ctotalpartial block, thesize (specified as the number of QAM cells) of the collection of fullcoded blocks for PLS2 that is carried in the current frame-group. Thisvalue is constant during the entire duration of the current frame-group.

PLS2_STAT_SIZE_BIT: This 14-bit field indicates the size, in bits, ofthe PLS2-STAT for the current frame-group. This value is constant duringthe entire duration of the current frame-group.

PLS2_DYN_SIZE_BIT: This 14-bit field indicates the size, in bits, of thePLS2-DYN for the current frame-group. This value is constant during theentire duration of the current frame-group.

PLS2_REP_FLAG: This 1-bit flag indicates whether the PLS2 repetitionmode is used in the current frame-group. When this field is set to value‘1’, the PLS2 repetition mode is activated. When this field is set tovalue ‘0’, the PLS2 repetition mode is deactivated.

PLS2_REP_SIZE_CELL: This 15-bit field indicates Ctotal_partial_block,the size (specified as the number of QAM cells) of the collection ofpartial coded blocks for PLS2 carried in every frame of the currentframe-group, when PLS2 repetition is used. If repetition is not used,the value of this field is equal to 0. This value is constant during theentire duration of the current frame-group.

PLS2_NEXT_FEC_TYPE: This 2-bit field indicates the FEC type used forPLS2 that is carried in every frame of the next frame-group. The FECtype is signaled according to the table 10.

PLS2_NEXT_MOD: This 3-bit field indicates the modulation type used forPLS2 that is carried in every frame of the next frame-group. Themodulation type is signaled according to the table 11.

PLS2_NEXT_REP_FLAG: This 1-bit flag indicates whether the PLS2repetition mode is used in the next frame-group. When this field is setto value ‘1’, the PLS2 repetition mode is activated. When this field isset to value ‘0’, the PLS2 repetition mode is deactivated.

PLS2_NEXT_REP_SIZE_CELL: This 15-bit field indicates Ctotal_full_block,The size (specified as the number of QAM cells) of the collection offull coded blocks for PLS2 that is carried in every frame of the nextframe-group, when PLS2 repetition is used. If repetition is not used inthe next frame-group, the value of this field is equal to 0. This valueis constant during the entire duration of the current frame-group.

PLS2_NEXT_REP_STAT_SIZE_BIT: This 14-bit field indicates the size, inbits, of the PLS2-STAT for the next frame-group. This value is constantin the current frame-group.

PLS2_NEXT_REP_DYN_SIZE_BIT: This 14-bit field indicates the size, inbits, of the PLS2-DYN for the next frame-group. This value is constantin the current frame-group.

PLS2_AP_MODE: This 2-bit field indicates whether additional parity isprovided for PLS2 in the current frame-group. This value is constantduring the entire duration of the current frame-group. The below table12 gives the values of this field. When this field is set to ‘00’,additional parity is not used for the PLS2 in the current frame-group.

TABLE 12 Value PLS2-AP mode 00 AP is not provided 01 AP1 mode 10~11Reserved

PLS2_AP_SIZE_CELL: This 15-bit field indicates the size (specified asthe number of QAM cells) of the additional parity bits of the PLS2. Thisvalue is constant during the entire duration of the current frame-group.

PLS2_NEXT_AP_MODE: This 2-bit field indicates whether additional parityis provided for PLS2 signaling in every frame of next frame-group. Thisvalue is constant during the entire duration of the current frame-group.The table 12 defines the values of this field

PLS2_NEXT_AP_SIZE_CELL: This 15-bit field indicates the size (specifiedas the number of QAM cells) of the additional parity bits of the PLS2 inevery frame of the next frame-group. This value is constant during theentire duration of the current frame-group.

RESERVED: This 32-bit field is reserved for future use.

CRC_32: A 32-bit error detection code, which is applied to the entirePLS1 signaling.

FIG. 14 illustrates PLS2 data according to an embodiment of the presentinvention.

FIG. 14 illustrates PLS2-STAT data of the PLS2 data. The PLS2-STAT dataare the same within a frame-group, while the PLS2-DYN data provideinformation that is specific for the current frame.

The details of fields of the PLS2-STAT data are as follows:

FIC_FLAG: This 1-bit field indicates whether the FIC is used in thecurrent frame-group. If this field is set to ‘1’, the FIC is provided inthe current frame. If this field set to ‘0’, the FIC is not carried inthe current frame. This value is constant during the entire duration ofthe current frame-group.

AUX_FLAG: This 1-bit field indicates whether the auxiliary stream(s) isused in the current frame-group. If this field is set to ‘1’, theauxiliary stream is provided in the current frame. If this field set to‘0’, the auxiliary stream is not carried in the current frame. Thisvalue is constant during the entire duration of current frame-group.

NUM_DP: This 6-bit field indicates the number of DPs carried within thecurrent frame. The value of this field ranges from 1 to 64, and thenumber of DPs is NUM_DP+1.

DP_ID: This 6-bit field identifies uniquely a DP within a PHY profile.

DP_TYPE: This 3-bit field indicates the type of the DP. This is signaledaccording to the below table 13.

TABLE 13 Value DP Type 000 DP Type 1 001 DP Type 2 010~111 reserved

DP_GROUP_ID: This 8-bit field identifies the DP group with which thecurrent DP is associated. This can be used by a receiver to access theDPs of the service components associated with a particular service,which will have the same DP_GROUP_ID.

BASE_DP_ID: This 6-bit field indicates the DP carrying service signalingdata (such as PSI/SI) used in the Management layer. The DP indicated byBASE_DP_ID may be either a normal DP carrying the service signaling dataalong with the service data or a dedicated DP carrying only the servicesignaling data.

DP_FEC_TYPE: This 2-bit field indicates the FEC type used by theassociated DP. The FEC type is signaled according to the below table 14.

TABLE 14 Value FEC_TYPE 00 16K LDPC 01 64K LDPC 10~11 Reserved

DP_COD: This 4-bit field indicates the code rate used by the associatedDP. The code rate is signaled according to the below table 15.

TABLE 15 Value Code rate 0000  5/15 0001  6/15 0010  7/15 0011  8/150100  9/15 0101 10/15 0110 11/15 0111 12/15 1000 13/15 1001~1111Reserved

DP_MOD: This 4-bit field indicates the modulation used by the associatedDP. The modulation is signaled according to the below table 16.

TABLE 16 Value Modulation 0000 QPSK 0001 QAM-16 0010 NUQ-64 0011 NUQ-2560100 NUQ-1024 0101 NUC-16 0110 NUC-64 0111 NUC-256 1000 NUC-10241001~111 reserved

DP_SSD_FLAG: This 1-bit field indicates whether the SSD mode is used inthe associated DP. If this field is set to value ‘1’, SSD is used. Ifthis field is set to value ‘0’, SSD is not used.

The following field appears only if PHY_PROFILE is equal to ‘010’, whichindicates the advanced profile:

DP_MIMO: This 3-bit field indicates which type of MIMO encoding processis applied to the associated DP. The type of MIMO encoding process issignaled according to the table 17.

TABLE 17 Value MIMO encoding 000 FR-SM 001 FRFD-SM 010~111 reserved

DP_TI_TYPE: This 1-bit field indicates the type of time-interleaving. Avalue of ‘0’ indicates that one TI group corresponds to one frame andcontains one or more TI-blocks. A value of ‘1’ indicates that one TIgroup is carried in more than one frame and contains only one TI-block.

DP_TI_LENGTH: The use of this 2-bit field (the allowed values are only1, 2, 4, 8) is determined by the values set within the DP_TI_TYPE fieldas follows:

If the DP_TI_TYPE is set to the value ‘1’, this field indicates PI, thenumber of the frames to which each TI group is mapped, and there is oneTI-block per TI group (NTI=1). The allowed PI values with 2-bit fieldare defined in the below table 18.

If the DP_TI_TYPE is set to the value ‘0’, this field indicates thenumber of TI-blocks NTI per TI group, and there is one TI group perframe (PI=1). The allowed PI values with 2-bit field are defined in thebelow table 18.

TABLE 18 2-bit field P_(I) N_(TI) 00 1 1 01 2 2 10 4 3 11 8 4

DP_FRAME_INTERVAL: This 2-bit field indicates the frame interval (HUMP)within the frame-group for the associated DP and the allowed values are1, 2, 4, 8 (the corresponding 2-bit field is ‘00’, ‘01’, ‘10’, or ‘11’,respectively). For DPs that do not appear every frame of theframe-group, the value of this field is equal to the interval betweensuccessive frames. For example, if a DP appears on the frames 1, 5, 9,13, etc., this field is set to ‘4’. For DPs that appear in every frame,this field is set to ‘1’.

DP_TI_BYPASS: This 1-bit field determines the availability of timeinterleaver. If time interleaving is not used for a DP, it is set to‘1’. Whereas if time interleaving is used it is set to ‘0’.

DP_FIRST_FRAME_IDX: This 5-bit field indicates the index of the firstframe of the super-frame in which the current DP occurs. The value ofDP_FIRST_FRAME_IDX ranges from 0 to 31.

DP_NUM_BLOCK_MAX: This 10-bit field indicates the maximum value ofDP_NUM_BLOCKS for this DP. The value of this field has the same range asDP_NUM_BLOCKS.

DP_PAYLOAD_TYPE: This 2-bit field indicates the type of the payload datacarried by the given DP. DP_PAYLOAD_TYPE is signaled according to thebelow table 19.

TABLE 19 Value Payload Type 00 TS. 01 IP 10 GS 11 reserved

DP_INBAND_MODE: This 2-bit field indicates whether the current DPcarries in-band signaling information. The in-band signaling type issignaled according to the below table 20.

TABLE 20 Value In-band mode 00 In-band signaling is not carried. 01INBAND-PLS is carried only 10 INBAND-ISSY is carried only 11 INBAND-PLSand INBAND-ISSY are carried

DP_PROTOCOL_TYPE: This 2-bit field indicates the protocol type of thepayload carried by the given DP. It is signaled according to the belowtable 21 when input payload types are selected.

TABLE 21 If DP_ If DP_ If DP_ PAYLOAD_TYPE PAYLOAD_TYPE PAYLOAD_TYPEValue Is TS Is IP Is GS 00 MPEG2-TS IPv4 (Note) 01 Reserved IPv6Reserved 10 Reserved Reserved Reserved 11 Reserved Reserved Reserved

DP_CRC_MODE: This 2-bit field indicates whether CRC encoding is used inthe Input Formatting block. The CRC mode is signaled according to thebelow table 22.

TABLE 22 Value CRC mode 00 Not used 01 CRC-8 10 CRC-16 11 CRC-32

DNP_MODE: This 2-bit field indicates the null-packet deletion mode usedby the associated DP when DP_PAYLOAD_TYPE is set to TS (‘00’). DNP_MODEis signaled according to the below table 23. If DP_PAYLOAD_TYPE is notTS (‘00’), DNP_MODE is set to the value ‘00’.

TABLE 23 Value Null-packet deletion mode 00 Not used 01 DNP-NORMAL 10DNP-OFFSET 11 reserved

ISSY_MODE: This 2-bit field indicates the ISSY mode used by theassociated DP when DP_PAYLOAD_TYPE is set to TS (‘00’). The ISSY_MODE issignaled according to the below table 24 If DP_PAYLOAD_TYPE is not TS(‘00’), ISSY_MODE is set to the value ‘00’.

TABLE 24 Value ISSY mode 00 Not used 01 ISSY-UP 10 ISSY-BBF 11 reserved

HC_MODE_TS: This 2-bit field indicates the TS header compression modeused by the associated DP when DP_PAYLOAD_TYPE is set to TS (‘00’). TheHC_MODE_TS is signaled according to the below table 25.

TABLE 25 Value Header compression mode 00 HC_MODE_TS 1 01 HC_MODE_TS 210 HC_MODE_TS 3 11 HC_MODE_TS 4

HC_MODE_IP: This 2-bit field indicates the IP header compression modewhen DP_PAYLOAD_TYPE is set to IP (‘01’). The HC_MODE_IP is signaledaccording to the below table 26.

TABLE 26 Value Header compression mode 00 No compression 01 HC_MODE_IP 110~11 reserved

PID: This 13-bit field indicates the PID number for TS headercompression when DP_PAYLOAD_TYPE is set to TS (‘00’) and HC_MODE_TS isset to ‘01’ or ‘10’.

RESERVED: This 8-bit field is reserved for future use.

The following field appears only if FIC_FLAG is equal to ‘1’:

FIC_VERSION: This 8-bit field indicates the version number of the FIC.

FIC_LENGTH_BYTE: This 13-bit field indicates the length, in bytes, ofthe FIC.

RESERVED: This 8-bit field is reserved for future use.

The following field appears only if AUX_FLAG is equal to ‘1’:

NUM_AUX: This 4-bit field indicates the number of auxiliary streams.Zero means no auxiliary streams are used.

AUX_CONFIG_RFU: This 8-bit field is reserved for future use.

AUX_STREAM_TYPE: This 4-bit is reserved for future use for indicatingthe type of the current auxiliary stream.

AUX_PRIVATE_CONFIG: This 28-bit field is reserved for future use forsignaling auxiliary streams.

FIG. 15 illustrates PLS2 data according to another embodiment of thepresent invention.

FIG. 15 illustrates PLS2-DYN data of the PLS2 data. The values of thePLS2-DYN data may change during the duration of one frame-group, whilethe size of fields remains constant.

The details of fields of the PLS2-DYN data are as follows:

FRAME_INDEX: This 5-bit field indicates the frame index of the currentframe within the super-frame. The index of the first frame of thesuper-frame is set to ‘0’.

PLS_CHANGE_COUNTER: This 4-bit field indicates the number ofsuper-frames ahead where the configuration will change. The nextsuper-frame with changes in the configuration is indicated by the valuesignaled within this field. If this field is set to the value ‘0000’, itmeans that no scheduled change is foreseen: e.g., value ‘1’ indicatesthat there is a change in the next super-frame.

FIC_CHANGE_COUNTER: This 4-bit field indicates the number ofsuper-frames ahead where the configuration (i.e., the contents of theFIC) will change. The next super-frame with changes in the configurationis indicated by the value signaled within this field. If this field isset to the value ‘0000’, it means that no scheduled change is foreseen:e.g. value ‘0001’ indicates that there is a change in the nextsuper-frame.

RESERVED: This 16-bit field is reserved for future use.

The following fields appear in the loop over NUM_DP, which describe theparameters associated with the DP carried in the current frame.

DP_ID: This 6-bit field indicates uniquely the DP within a PHY profile.

DP_START: This 15-bit (or 13-bit) field indicates the start position ofthe first of the DPs using the DPU addressing scheme. The DP_START fieldhas differing length according to the PHY profile and FFT size as shownin the below table 27.

TABLE 27 DP_START field size PHY profile 64K 16K Base 13 bit 15 bitHandheld — 13 bit Advanced 13 bit 15 bit

DP_NUM_BLOCK: This 10-bit field indicates the number of FEC blocks inthe current TI group for the current DP. The value of DP_NUM_BLOCKranges from 0 to 1023.

RESERVED: This 8-bit field is reserved for future use.

The following fields indicate the FIC parameters associated with theEAC.

EAC_FLAG: This 1-bit field indicates the existence of the EAC in thecurrent frame. This bit is the same value as the EAC_FLAG in thepreamble.

EAS_WAKE_UP_VERSION_NUM: This 8-bit field indicates the version numberof a wake-up indication.

If the EAC_FLAG field is equal to ‘1’, the following 12 bits areallocated for EAC_LENGTH_BYTE field. If the EAC_FLAG field is equal to‘0’, the following 12 bits are allocated for EAC_COUNTER.

EAC_LENGTH_BYTE: This 12-bit field indicates the length, in byte, of theEAC.

EAC_COUNTER: This 12-bit field indicates the number of the frames beforethe frame where the EAC arrives.

The following field appears only if the AUX_FLAG field is equal to ‘1’:

AUX_PRIVATE_DYN: This 48-bit field is reserved for future use forsignaling auxiliary streams. The meaning of this field depends on thevalue of AUX_STREAM_TYPE in the configurable PLS2-STAT.

CRC_32: A 32-bit error detection code, which is applied to the entirePLS2.

FIG. 16 illustrates a logical structure of a frame according to anembodiment of the present invention.

As above mentioned, the PLS, EAC, FIC, DPs, auxiliary streams and dummycells are mapped into the active carriers of the OFDM symbols in theframe. The PLS1 and PLS2 are first mapped into one or more FSS(s). Afterthat, EAC cells, if any, are mapped immediately following the PLS field,followed next by FIC cells, if any. The DPs are mapped next after thePLS or EAC, FIC, if any. Type 1 DPs follows first, and Type 2 DPs next.The details of a type of the DP will be described later. In some case,DPs may carry some special data for EAS or service signaling data. Theauxiliary stream or streams, if any, follow the DPs, which in turn arefollowed by dummy cells. Mapping them all together in the abovementioned order, i.e. PLS, EAC, FIC, DPs, auxiliary streams and dummydata cells exactly fill the cell capacity in the frame.

FIG. 17 illustrates PLS mapping according to an embodiment of thepresent invention.

PLS cells are mapped to the active carriers of FSS(s). Depending on thenumber of cells occupied by PLS, one or more symbols are designated asFSS(s), and the number of FSS(s) NFSS is signaled by NUM_FSS in PLS1.The FSS is a special symbol for carrying PLS cells. Since robustness andlatency are critical issues in the PLS, the FSS(s) has higher density ofpilots allowing fast synchronization and frequency-only interpolationwithin the FSS.

PLS cells are mapped to active carriers of the NFSS FSS(s) in a top-downmanner as shown in an example in FIG. 17. The PLS1 cells are mappedfirst from the first cell of the first FSS in an increasing order of thecell index. The PLS2 cells follow immediately after the last cell of thePLS1 and mapping continues downward until the last cell index of thefirst FSS. If the total number of required PLS cells exceeds the numberof active carriers of one FSS, mapping proceeds to the next FSS andcontinues in exactly the same manner as the first FSS.

After PLS mapping is completed, DPs are carried next. If EAC, FIC orboth are present in the current frame, they are placed between PLS and“normal” DPs.

FIG. 18 illustrates EAC mapping according to an embodiment of thepresent invention.

EAC is a dedicated channel for carrying EAS messages and links to theDPs for EAS. EAS support is provided but EAC itself may or may not bepresent in every frame. EAC, if any, is mapped immediately after thePLS2 cells. EAC is not preceded by any of the FIC, DPs, auxiliarystreams or dummy cells other than the PLS cells. The procedure ofmapping the EAC cells is exactly the same as that of the PLS.

The EAC cells are mapped from the next cell of the PLS2 in increasingorder of the cell index as shown in the example in FIG. 18. Depending onthe EAS message size, EAC cells may occupy a few symbols, as shown inFIG. 18.

EAC cells follow immediately after the last cell of the PLS2, andmapping continues downward until the last cell index of the last FSS. Ifthe total number of required EAC cells exceeds the number of remainingactive carriers of the last FSS mapping proceeds to the next symbol andcontinues in exactly the same manner as FSS(s). The next symbol formapping in this case is the normal data symbol, which has more activecarriers than a FSS.

After EAC mapping is completed, the FIC is carried next, if any exists.If FIC is not transmitted (as signaled in the PLS2 field), DPs followimmediately after the last cell of the EAC.

FIG. 19 illustrates FIC mapping according to an embodiment of thepresent invention.

(a) shows an example mapping of FIC cell without EAC and (b) shows anexample mapping of FIC cell with EAC.

FIC is a dedicated channel for carrying cross-layer information toenable fast service acquisition and channel scanning. This informationprimarily includes channel binding information between DPs and theservices of each broadcaster. For fast scan, a receiver can decode FICand obtain information such as broadcaster ID, number of services, andBASE_DP_ID. For fast service acquisition, in addition to FIC, base DPcan be decoded using BASE_DP_ID. Other than the content it carries, abase DP is encoded and mapped to a frame in exactly the same way as anormal DP. Therefore, no additional description is required for a baseDP. The FIC data is generated and consumed in the Management Layer. Thecontent of FIC data is as described in the Management Layerspecification.

The FIC data is optional and the use of FIC is signaled by the FIC_FLAGparameter in the static part of the PLS2. If FIC is used, FIC_FLAG isset to ‘1’ and the signaling field for FIC is defined in the static partof PLS2. Signaled in this field are FIC_VERSION, and FIC_LENGTH_BYTE.FIC uses the same modulation, coding and time interleaving parameters asPLS2. FIC shares the same signaling parameters such as PLS2_MOD andPLS2_FEC. FIC data, if any, is mapped immediately after PLS2 or EAC ifany. FIC is not preceded by any normal DPs, auxiliary streams or dummycells. The method of mapping FIC cells is exactly the same as that ofEAC which is again the same as PLS.

Without EAC after PLS, FIC cells are mapped from the next cell of thePLS2 in an increasing order of the cell index as shown in an example in(a). Depending on the FIC data size, FIC cells may be mapped over a fewsymbols, as shown in (b).

FIC cells follow immediately after the last cell of the PLS2, andmapping continues downward until the last cell index of the last FSS. Ifthe total number of required FIC cells exceeds the number of remainingactive carriers of the last FSS, mapping proceeds to the next symbol andcontinues in exactly the same manner as FSS(s). The next symbol formapping in this case is the normal data symbol which has more activecarriers than a FSS.

If EAS messages are transmitted in the current frame, EAC precedes FIC,and FIC cells are mapped from the next cell of the EAC in an increasingorder of the cell index as shown in (b).

After FIC mapping is completed, one or more DPs are mapped, followed byauxiliary streams, if any, and dummy cells.

FIG. 20 illustrates a type of DP according to an embodiment of thepresent invention.

(a) shows type 1 DP and (b) shows type 2 DP.

After the preceding channels, i.e., PLS, EAC and FIC, are mapped, cellsof the DPs are mapped. A DP is categorized into one of two typesaccording to mapping method:

Type 1 DP: DP is mapped by TDM.

Type 2 DP: DP is mapped by FDM.

The type of DP is indicated by DP_TYPE field in the static part of PLS2.FIG. 20 illustrates the mapping orders of Type 1 DPs and Type 2 DPs.Type 1 DPs are first mapped in the increasing order of cell index, andthen after reaching the last cell index, the symbol index is increasedby one. Within the next symbol, the DP continues to be mapped in theincreasing order of cell index starting from p=0. With a number of DPsmapped together in one frame, each of the Type 1 DPs are grouped intime, similar to TDM multiplexing of DPs.

Type 2 DPs are first mapped in the increasing order of symbol index, andthen after reaching the last OFDM symbol of the frame, the cell indexincreases by one and the symbol index rolls back to the first availablesymbol and then increases from that symbol index. After mapping a numberof DPs together in one frame, each of the Type 2 DPs are grouped infrequency together, similar to FDM multiplexing of DPs.

Type 1 DPs and Type 2 DPs can coexist in a frame if needed with onerestriction; Type 1 DPs always precede Type 2 DPs. The total number ofOFDM cells carrying Type 1 and Type 2 DPs cannot exceed the total numberof OFDM cells available for transmission of DPs:

$\begin{matrix}{{D_{{DP}\; 1} + D_{{DP}\; 2}} \leq D_{DP}} & \left\lbrack {{Math}\mspace{14mu}{Figure}\mspace{14mu} 2} \right\rbrack\end{matrix}$

where D_(DP1) is the number of OFDM cells occupied by Type 1 DPs,D_(DP2) is the number of cells occupied by Type 2 DPs. Since PLS, EAC,FIC are all mapped in the same way as Type 1 DP, they all follow “Type 1mapping rule”. Hence, overall, Type 1 mapping always precedes Type 2mapping.

FIG. 21 illustrates DP mapping according to an embodiment of the presentinvention.

(a) shows an addressing of OFDM cells for mapping type 1 DPs and (b)shows an addressing of OFDM cells for mapping for type 2 DPs.

Addressing of OFDM cells for mapping Type 1 DPs (0, . . . , DDP1-1) isdefined for the active data cells of Type 1 DPs. The addressing schemedefines the order in which the cells from the TIs for each of the Type 1DPs are allocated to the active data cells. It is also used to signalthe locations of the DPs in the dynamic part of the PLS2.

Without EAC and FIC, address 0 refers to the cell immediately followingthe last cell carrying PLS in the last FSS. If EAC is transmitted andFIC is not in the corresponding frame, address 0 refers to the cellimmediately following the last cell carrying EAC. If FIC is transmittedin the corresponding frame, address 0 refers to the cell immediatelyfollowing the last cell carrying FIC. Address 0 for Type 1 DPs can becalculated considering two different cases as shown in (a). In theexample in (a), PLS, EAC and FIC are assumed to be all transmitted.Extension to the cases where either or both of EAC and FIC are omittedis straightforward. If there are remaining cells in the FSS aftermapping all the cells up to FIC as shown on the left side of (a).

Addressing of OFDM cells for mapping Type 2 DPs (0, . . . , DDP2-1) isdefined for the active data cells of Type 2 DPs. The addressing schemedefines the order in which the cells from the TIs for each of the Type 2DPs are allocated to the active data cells. It is also used to signalthe locations of the DPs in the dynamic part of the PLS2.

Three slightly different cases are possible as shown in (b). For thefirst case shown on the left side of (b), cells in the last FSS areavailable for Type 2 DP mapping. For the second case shown in themiddle, FIC occupies cells of a normal symbol, but the number of FICcells on that symbol is not larger than CFSS. The third case, shown onthe right side in (b), is the same as the second case except that thenumber of FIC cells mapped on that symbol exceeds CFSS.

The extension to the case where Type 1 DP(s) precede Type 2 DP(s) isstraightforward since PLS, EAC and FIC follow the same “Type 1 mappingrule” as the Type 1 DP(s).

A data pipe unit (DPU) is a basic unit for allocating data cells to a DPin a frame.

A DPU is defined as a signaling unit for locating DPs in a frame. A CellMapper 7010 may map the cells produced by the TIs for each of the DPs. ATime interleaver 5050 outputs a series of TI-blocks and each TI-blockcomprises a variable number of XFECBLOCKs which is in turn composed of aset of cells. The number of cells in an XFECBLOCK, Ncells, is dependenton the FECBLOCK size, Nldpc, and the number of transmitted bits perconstellation symbol. A DPU is defined as the greatest common divisor ofall possible values of the number of cells in a XFECBLOCK, Ncells,supported in a given PHY profile. The length of a DPU in cells isdefined as LDPU. Since each PHY profile supports different combinationsof FECBLOCK size and a different number of bits per constellationsymbol, LDPU is defined on a PHY profile basis.

FIG. 22 illustrates an FEC structure according to an embodiment of thepresent invention.

FIG. 22 illustrates an FEC structure according to an embodiment of thepresent invention before bit interleaving. As above mentioned, Data FECencoder may perform the FEC encoding on the input BBF to generateFECBLOCK procedure using outer coding (BCH), and inner coding (LDPC).The illustrated FEC structure corresponds to the FECBLOCK. Also, theFECBLOCK and the FEC structure have same value corresponding to a lengthof LDPC codeword.

The BCH encoding is applied to each BBF (Kbch bits), and then LDPCencoding is applied to BCH-encoded BBF (Kldpc bits=Nbch bits) asillustrated in FIG. 22.

The value of Nldpc is either 64800 bits (long FECBLOCK) or 16200 bits(short FECBLOCK).

The below table 28 and table 29 show FEC encoding parameters for a longFECBLOCK and a short FECBLOCK, respectively.

TABLE 28 BCH error LDPC correction Rate N_(ldpc) K_(ldpc) K_(bch)capability N_(bch)-K_(bch)  5/15 64800 21600 21408 12 192  6/15 2592025728  7/15 30240 30048  8/15 34560 34368  9/15 38880 38688 10/15 4320043008 11/15 47520 47328 12/15 51840 51648 13/15 56160 55968

TABLE 29 BCH error LDPC correction Rate N_(ldpc) K_(ldpc) K_(bch)capability N_(bch)-K_(bch)  5/15 16200 5400 5232 12 168  6/15 6480 6312 7/15 7560 7392  8/15 8640 8472  9/15 9720 9552 10/15 10800 10632 11/1511880 11712 12/15 12960 12792 13/15 14040 13872

The details of operations of the BCH encoding and LDPC encoding are asfollows:

A 12-error correcting BCH code is used for outer encoding of the BBF.The BCH generator polynomial for short FECBLOCK and long FECBLOCK areobtained by multiplying together all polynomials.

LDPC code is used to encode the output of the outer BCH encoding. Togenerate a completed Bldpc (FECBLOCK), Pldpc (parity bits) is encodedsystematically from each Ildpc (BCH-encoded BBF), and appended to Ildpc.The completed Bldpc (FECBLOCK) are expressed as follow Math figure.

$\begin{matrix}{B_{ldpc} = {\left\lbrack {I_{ldpc}\mspace{14mu} P_{ldpc}} \right\rbrack = \left\lbrack {i_{0},i_{1},\ldots\;,i_{K_{ldpc} - 1},p_{0},p_{1},\ldots\;,p_{N_{ldpc} - K_{ldpc} - 1}} \right\rbrack}} & \left\lbrack {{Math}\mspace{14mu}{Figure}\mspace{14mu} 3} \right\rbrack\end{matrix}$

The parameters for long FECBLOCK and short FECBLOCK are given in theabove table 28 and 29, respectively.

The detailed procedure to calculate Nldpc−Kldpc parity bits for longFECBLOCK, is as follows:

1) Initialize the parity bits,

$\begin{matrix}{p_{0} = {p_{1} = {p_{2} = {\ldots = {p_{N_{ldpc} - K_{ldpc} - 1} = 0}}}}} & \left\lbrack {{Math}\mspace{14mu}{Figure}\mspace{14mu} 4} \right\rbrack\end{matrix}$

2) Accumulate the first information bit—i₀, at parity bit addressesspecified in the first row of an addresses of parity check matrix. Thedetails of addresses of parity check matrix will be described later. Forexample, for rate 13/15:

$\begin{matrix}{{p_{983} = {p_{983} \oplus i_{0}}}{p_{2815} = {p_{2815} \oplus i_{0}}}{p_{4837} = {p_{4837} \oplus i_{0}}}{p_{4989} = {p_{4989} \oplus i_{0}}}{p_{6138} = {p_{6138} \oplus i_{0}}}{p_{6458} = {p_{6458} \oplus i_{0}}}{p_{6921} = {p_{6921} \oplus i_{0}}}{p_{6974} = {p_{6974} \oplus i_{0}}}{p_{7572} = {p_{7572} \oplus i_{0}}}{p_{8260} = {p_{8260} \oplus i_{0}}}{p_{8496} = {p_{8496} \oplus i_{0}}}} & \left\lbrack {{Math}\mspace{14mu}{Figure}\mspace{14mu} 5} \right\rbrack\end{matrix}$

3) For the next 359 information bits, i_(s), s=1, 2, . . . , 359accumulate is at parity bit addresses using following Math figure.

$\begin{matrix}{\left\{ {x + {\left( {s\mspace{14mu}{mod}\mspace{14mu} 360} \right) \times Q_{ldpc}}} \right\}\mspace{14mu}{mod}\mspace{14mu}\left( {N_{ldpc} - K_{ldpc}} \right)} & \left\lbrack {{Math}\mspace{14mu}{Figure}\mspace{14mu} 6} \right\rbrack\end{matrix}$

where x denotes the address of the parity bit accumulator correspondingto the first bit i0, and Qldpc is a code rate dependent constantspecified in the addresses of parity check matrix. Continuing with theexample, Qldpc=24 for rate 13/15, so for information bit i1, thefollowing operations are performed:

$\begin{matrix}{{p_{1007} = {p_{1007} \oplus i_{1}}}{p_{2839} = {p_{2839} \oplus i_{1}}}{p_{4861} = {p_{4861} \oplus i_{1}}}{p_{5013} = {p_{5013} \oplus i_{1}}}{p_{6162} = {p_{6162} \oplus i_{1}}}{p_{6482} = {p_{6482} \oplus i_{1}}}{p_{6945} = {p_{6945} \oplus i_{1}}}{p_{6998} = {p_{6998} \oplus i_{1}}}{p_{7596} = {p_{7596} \oplus i_{1}}}{p_{8284} = {p_{8284} \oplus i_{1}}}{p_{8520} = {p_{8520} \oplus i_{1}}}} & \left\lbrack {{Math}\mspace{14mu}{Figure}\mspace{14mu} 7} \right\rbrack\end{matrix}$

4) For the 361st information bit i360, the addresses of the parity bitaccumulators are given in the second row of the addresses of paritycheck matrix. In a similar manner the addresses of the parity bitaccumulators for the following 359 information bits is, s=361, 362, . .. , 719 are obtained using the Math FIG. 6, where x denotes the addressof the parity bit accumulator corresponding to the information bit i360,i.e., the entries in the second row of the addresses of parity checkmatrix.

5) In a similar manner, for every group of 360 new information bits, anew row from addresses of parity check matrixes used to find theaddresses of the parity bit accumulators.

After all of the information bits are exhausted, the final parity bitsare obtained as follows:

6) Sequentially perform the following operations starting with i=1.

$\begin{matrix}{{p_{i} = {p_{i} \oplus p_{i - 1}}},{i = 1},2,\ldots\;,{N_{ldpc} - K_{ldpc} - 1}} & \left\lbrack {{Math}\mspace{14mu}{Figure}\mspace{14mu} 8} \right\rbrack\end{matrix}$

where final content of p_(i), i=0, 1, . . . N_(ldpc)−K_(ldpc)−1 is equalto the parity bit p_(i).

TABLE 30 Code Rate Q_(ldpc)  5/15 120  6/15 108  7/15  96  8/15  84 9/15  72 10/15  60 11/15  48 12/15  36 13/15  24

This LDPC encoding procedure for a short FECBLOCK is in accordance witht LDPC encoding procedure for the long FECBLOCK, except replacing thetable 30 with table 31, and replacing the addresses of parity checkmatrix for the long FECBLOCK with the addresses of parity check matrixfor the short FECBLOCK.

TABLE 31 Code Rate Q_(ldpc)  5/15 30  6/15 27  7/15 24  8/15 21  9/15 1810/15 15 11/15 12 12/15 9 13/15 6

FIG. 23 illustrates a bit interleaving according to an embodiment of thepresent invention.

The outputs of the LDPC encoder are bit-interleaved, which consists ofparity interleaving followed by Quasi-Cyclic Block (QCB) interleavingand inner-group interleaving.

(a) shows Quasi-Cyclic Block (QCB) interleaving and (b) showsinner-group interleaving.

The FECBLOCK may be parity interleaved. At the output of the parityinterleaving, the LDPC codeword consists of 180 adjacent QC blocks in along FECBLOCK and 45 adjacent QC blocks in a short FECBLOCK. Each QCblock in either a long or short FECBLOCK consists of 360 bits. Theparity interleaved LDPC codeword is interleaved by QCB interleaving. Theunit of QCB interleaving is a QC block. The QC blocks at the output ofparity interleaving are permutated by QCB interleaving as illustrated inFIG. 23, where Ncells=64800/η mod or 16200/η mod according to theFECBLOCK length. The QCB interleaving pattern is unique to eachcombination of modulation type and LDPC code rate.

After QCB interleaving, inner-group interleaving is performed accordingto modulation type and order (η mod) which is defined in the below table32. The number of QC blocks for one inner-group, NQCB_IG, is alsodefined.

TABLE 32 Modulation type η_(mod) N_(QCB)_IG QAM-16  4 2 NUC-16  4 4NUQ-64  6 3 NUC-64  6 6 NUQ-256  8 4 NUC-256  8 8 NUQ-1024 10 5 NUC-102410 10

The inner-group interleaving process is performed with NQCB_IG QC blocksof the QCB interleaving output. Inner-group interleaving has a processof writing and reading the bits of the inner-group using 360 columns andNQCB_IG rows. In the write operation, the bits from the QCB interleavingoutput are written row-wise. The read operation is performed column-wiseto read out m bits from each row, where m is equal to 1 for NUC and 2for NUQ.

FIG. 24 illustrates a cell-word demultiplexing according to anembodiment of the present invention.

(a) shows a cell-word demultiplexing for 8 and 12 bpcu MIMO and (b)shows a cell-word demultiplexing for 10 bpcu MIMO.

Each cell word (c0,1, c1,1, . . . , cη mod-1,1) of the bit interleavingoutput is demultiplexed into (d1,0,m, d1,1,m . . . , d1,η mod-1,m) and(d2,0,m, d2,1,m . . . , d2η mod-1,m) as shown in (a), which describesthe cell-word demultiplexing process for one XFECBLOCK.

For the 10 bpcu MIMO case using different types of NUQ for MIMOencoding, the Bit Interleaver for NUQ-1024 is re-used. Each cell word(c0,1, c1,1, . . . , c9,1) of the Bit Interleaver output isdemultiplexed into (d1,0,m, d1,1,m . . . , d1,3,m) and (d2,0,m, d2,1,m .. . , d2,5,m), as shown in (b).

FIG. 25 illustrates a time interleaving according to an embodiment ofthe present invention.

(a) to (c) show examples of TI mode.

The time interleaver operates at the DP level. The parameters of timeinterleaving (TI) may be set differently for each DP.

The following parameters, which appear in part of the PLS2-STAT data,configure the TI:

DP_TI_TYPE (allowed values: 0 or 1): Represents the TI mode; ‘0’indicates the mode with multiple TI blocks (more than one TI block) perTI group. In this case, one TI group is directly mapped to one frame (nointer-frame interleaving). ‘1’ indicates the mode with only one TI blockper TI group. In this case, the TI block may be spread over more thanone frame (inter-frame interleaving).

DP_TI_LENGTH: If DP_TI_TYPE=‘0’, this parameter is the number of TIblocks NTI per TI group. For DP_TI_TYPE=‘1’, this parameter is thenumber of frames PI spread from one TI group.

DP_NUM_BLOCK_MAX (allowed values: 0 to 1023): Represents the maximumnumber of XFECBLOCKs per TI group.

DP_FRAME_INTERVAL (allowed values: 1, 2, 4, 8): Represents the number ofthe frames HUMP between two successive frames carrying the same DP of agiven PHY profile.

DP_TI_BYPASS (allowed values: 0 or 1): If time interleaving is not usedfor a DP, this parameter is set to ‘1’. It is set to ‘0’ if timeinterleaving is used.

Additionally, the parameter DP_NUM_BLOCK from the PLS2-DYN data is usedto represent the number of XFECBLOCKs carried by one TI group of the DP.

When time interleaving is not used for a DP, the following TI group,time interleaving operation, and TI mode are not considered. However,the Delay Compensation block for the dynamic configuration informationfrom the scheduler will still be required. In each DP, the XFECBLOCKsreceived from the SSD/MIMO encoding are grouped into TI groups. That is,each TI group is a set of an integer number of XFECBLOCKs and willcontain a dynamically variable number of XFECBLOCKs. The number ofXFECBLOCKs in the TI group of index n is denoted by NxBLOCK_Group(n) andis signaled as DP_NUM_BLOCK in the PLS2-DYN data. Note thatNxBLOCK_Group(n) may vary from the minimum value of 0 to the maximumvalue NxBLOCK_Group_MAX (corresponding to DP_NUM_BLOCK_MAX) of which thelargest value is 1023.

Each TI group is either mapped directly onto one frame or spread over PIframes. Each TI group is also divided into more than one TI blocks(NTI),where each TI block corresponds to one usage of time interleaver memory.The TI blocks within the TI group may contain slightly different numbersof XFECBLOCKs. If the TI group is divided into multiple TI blocks, it isdirectly mapped to only one frame. There are three options for timeinterleaving (except the extra option of skipping the time interleaving)as shown in the below table 33.

TABLE 33 Modes Descriptions Option-1 Each TI group contains one TI blockand is mapped directly to one frame as shown in (a). This option issignaled in the PLS2-STAT by DP_TI_TYPE = ‘0’ and DP_TI_LENGTH =‘1’(N_(TI) = 1). Option-2 Each TI group contains one TI block and ismapped to more than one frame. (b) shows an example, where one TI groupis mapped to two frames, i.e., DP_TI_LENGTH = ‘2’ (P_(I) = 2) andDP_FRAME_INTERVAL (I_(Jump) = 2). This provides greater time diversityfor low data-rate services. This option is signaled in the PLS2-STAT byDP_TI_TYPE = ‘1’. Option-3 Each TI group is divided into multiple TIblocks and is mapped directly to one frame as shown in (c). Each TIblock may use full TI memory, so as to provide the maximum bit-rate fora DP. This option is signaled in the PLS2-STAT signaling by DP_TI_TYPE =‘0’ and DP_TI_LENGTH = N_(TI), while P_(I) = 1.

In each DP, the TI memory stores the input XFECBLOCKs (output XFECBLOCKsfrom the SSD/MIMO encoding block). Assume that input XFECBLOCKs aredefined as

(d_(n, s, 0, 0), d_(n, s, 0, 1), … , d_(n, s, 0, N_(cells) − 1), d_(n, s, 1, 0), … , d_(n, s, 1, N_(cells) − 1), … , d_(n, s, N_(xBLOCK_TI)(n, s) − 1, 0), … , d_(n, s, N_(xBLOCK_TI)(n, s) − 1, N_(cells) − 1)),

where d_(n,s,r,q) is the qth cell of the rth XFECBLOCK in the sth TIblock of the nth TI group and represents the outputs of SSD and MIMOencodings as follows.

$d_{n,s,r,q} = \left\{ {\begin{matrix}f_{n,s,r,q} & {,{{the}\mspace{14mu}{output}\mspace{14mu}{of}\mspace{14mu}{SSD\cdots}\;{encoding}}} \\g_{n,s,r,q} & {,{{the}\mspace{14mu}{output}\mspace{14mu}{of}\mspace{14mu}{MIMO}\mspace{14mu}{encoding}}}\end{matrix}.} \right.$

In addition, assume that output XFECBLOCKs from the time interleaver aredefined as

(h_(n, s, 0), h_(n, s, 1), … , h_(n, s, i), … , h_(n, s, xBLOCK_TI (n, s) × N_(cells) − 1)),

where h_(n,s,i) is the ith output cell (for i=0, . . . ,N_(xBLOCK_TI)(n,s)×N_(cells)−1) in the sth TI block of the nth TI group.

Typically, the time interleaver will also act as a buffer for DP dataprior to the process of frame building. This is achieved by means of twomemory banks for each DP. The first TI-block is written to the firstbank. The second TI-block is written to the second bank while the firstbank is being read from and so on.

The TI is a twisted row-column block interleaver. For the sth TI blockof the nth TI group, the number of rows N_(r) of a TI memory is equal tothe number of cells N_(cells), i.e., N_(r)=N_(cells) while the number ofcolumns N_(c) is equal to the number N_(xBLOCK_TI)(n,s).

FIG. 26 illustrates the basic operation of a twisted row-column blockinterleaver according to an embodiment of the present invention.

shows a writing operation in the time interleaver and (b) shows areading operation in the time interleaver The first XFECBLOCK is writtencolumn-wise into the first column of the TI memory, and the secondXFECBLOCK is written into the next column, and so on as shown in (a).Then, in the interleaving array, cells are read out diagonal-wise.During diagonal-wise reading from the first row (rightwards along therow beginning with the left-most column) to the last row, N_(r) cellsare read out as shown in (b). In detail, assuming z_(n,s,i) (i=0, . . ., N_(r)N_(c)) as the TI memory cell position to be read sequentially,the reading process in such an interleaving array is performed bycalculating the row index R_(n,s,i), the column index C_(n,s,i), and theassociated twisting parameter T_(n,s,i) as follows expression.

$\begin{matrix}{{{GENERATE}\left( {R_{n,s,i},C_{n,s,i}} \right)} = \left\{ {{R_{n,s,i} = {{mod}\left( {i,N_{r}} \right)}},{T_{n,s,i} = {{mod}\left( {{S_{shift} \times R_{n,s,i}},N_{c}} \right)}},{C_{n,s,i} = {{mod}\left( {{T_{n,s,i} + \left\lfloor \frac{i}{N_{r}} \right\rfloor},N_{c}} \right)}}} \right\}} & \left\lbrack {{Math}\mspace{14mu}{Figure}\mspace{14mu} 9} \right\rbrack\end{matrix}$

where S_(shift) is a common shift value for the diagonal-wise readingprocess regardless of N_(xBLOCK_TI)(n,s), and it is determined byN_(xBLOCK_TI_MAX) given in the PLS2-STAT as follows expression.

$\begin{matrix}{{for}\mspace{14mu}\left\{ {\begin{matrix}{{N_{{{xBLOCK}\_{TI}}{\_{MAX}}}^{\prime} = {N_{{{xBLOCK}\_{TI}}{\_{MAX}}} + 1}},} & {{{if}\mspace{14mu} N_{{{xBLOCK}\_{TI}}{\_{MAX}}}{mod}\; 2} = 0} \\{{N_{{{xBLOCK}\_{TI}}{\_{MAX}}}^{\prime} = N_{{{xBLOCK}\_{TI}}{\_{MAX}}}},} & {{{if}\mspace{14mu} N_{{{xBLOCK}\_{TI}}{\_{MAX}}}{mod}\; 2} = 1}\end{matrix},{S_{shift} = \frac{N_{{{xBLOCK}\_{TI}}{\_{MAX}}}^{\prime} - 1}{2}}} \right.} & \left\lbrack {{Math}\mspace{14mu}{Figure}\mspace{14mu} 10} \right\rbrack\end{matrix}$

As a result, the cell positions to be read are calculated by acoordinate as z_(n,s,i)=N_(r)C_(n,s,i)+R_(n,s,i).

FIG. 27 illustrates an operation of a twisted row-column blockinterleaver according to another embodiment of the present invention.

More specifically, FIG. 27 illustrates the interleaving array in the TImemory for each TI group, including virtual XFECBLOCKs whenN_(xBLOCK_TI)(0,0)=3, N_(xBLOCK_TI)(1,0)=6, N_(xBLOCK_TI)(2,0)=5.

The variable number N_(xBLOCK_TI)(n,s)=N_(r) will be less than or equalto N′_(xBLOCK_TI_MAX). Thus, in order to achieve a single-memorydeinterleaving at the receiver side, regardless of N_(xBLOCK_TI)(n,s),the interleaving array for use in a twisted row-column block interleaveris set to the size of N_(r)×N_(c)=N_(cells)×N′_(xBLOCK_TI_MAX) byinserting the virtual XFECBLOCKs into the TI memory and the readingprocess is accomplished as follow expression.

$\begin{matrix}{{{p = 0};}{{{{for}\mspace{14mu} i} = 0};{i < {N_{cells}N_{{{xBLOCK}\_{TI}}{\_{MAX}}}^{\prime}}};{i = {i + 1}}}\left\{ {{{GENERATE}\left( {R_{n,s,i},C_{n,s,i}} \right)};{V_{i} = {{{N_{r}C_{n,s,j}} + {R_{n,s,j}{if}\mspace{14mu} V_{i}}} < {N_{cells}{N_{{xBLOCK}\_{TI}}\left( {n,s} \right)}\left\{ {{Z_{n,s,p} = V_{i}};{p = {p + 1}};} \right\}}}}} \right\}} & \left\lbrack {{Math}\mspace{14mu}{Figure}\mspace{14mu} 11} \right\rbrack\end{matrix}$

The number of TI groups is set to 3. The option of time interleaver issignaled in the PLS2-STAT data by DP_TI_TYPE=‘0’, DP_FRAME_INTERVAL=‘1’,and DP_TI_LENGTH=‘1’, i.e., NTI=1, IJUMP=1, and PI=1. The number ofXFECBLOCKs, each of which has Ncells=30 cells, per TI group is signaledin the PLS2-DYN data by NxBLOCK_TI(0,0)=3, NxBLOCK_TI(1,0)=6, andNxBLOCK_TI(2,0)=5, respectively. The maximum number of XFECBLOCK issignaled in the PLS2-STAT data by NxBLOCK_Group_MAX, which leads to└N_(xBLOCK_Group_MAX)/N_(TI)┘=N_(xBLOCK_TI_MAX)=6.

FIG. 28 illustrates a diagonal-wise reading pattern of a twistedrow-column block interleaver according to an embodiment of the presentinvention.

More specifically FIG. 28 shows a diagonal-wise reading pattern fromeach interleaving array with parameters of N′_(xBLOCK_TI_MAX)=7 andSshift=(7−1)/2=3. Note that in the reading process shown as pseudocodeabove, if V_(i)≥N_(cells)N_(xBLOCK_TI)(n,s), the value of Vi is skippedand the next calculated value of Vi is used.

FIG. 29 illustrates interleaved XFECBLOCKs from each interleaving arrayaccording to an embodiment of the present invention.

FIG. 29 illustrates the interleaved XFECBLOCKs from each interleavingarray with parameters of N′_(xBLOCK_TI_MAX)=7 and Sshift=3.

Hereinafter, a mobile terminal relating to the present invention will bedescribed in more detail with reference to the accompanying drawings.Noun suffixes such as “engine”, “module”, and “unit” for components indescription below are given or mixed in consideration of easiness inwriting the specification. That is, the noun suffixes themselves doesnot have respectively distinguishable meanings or roles.

A network topology will be described with reference to FIGS. 30 to 38according to an embodiment.

FIG. 30 is a block diagram illustrating the network topology accordingto the embodiment.

As shown in FIG. 30, the network topology includes a content providingserver 10, a content recognizing service providing server 20, amultichannel video distributing server 30, an enhanced serviceinformation providing server 40, a plurality of enhanced serviceproviding servers 50, a broadcast receiving device 60, a network 70, anda video display device 100.

The content providing server 10 may correspond to a broadcasting stationand broadcasts a broadcast signal including main audio-visual contents.The broadcast signal may further include enhanced services. The enhancedservices may or may not relate to main audio-visual contents. Theenhanced services may have formats such as service information,metadata, additional data, compiled execution files, web applications,Hypertext Markup Language (HTML) documents, XML documents, CascadingStyle Sheet (CSS) documents, audio files, video files, ATSC 2.0contents, and addresses such as Uniform Resource Locator (URL). Theremay be at least one content providing server.

The content recognizing service providing server 20 provides a contentrecognizing service that allows the video display device 100 torecognize content on the basis of main audio-visual content. The contentrecognizing service providing server 20 may or may not edit the mainaudio-visual content. There may be at least one content recognizingservice providing server.

The content recognizing service providing server 20 may be a watermarkserver that edits the main audio-visual content to insert a visiblewatermark, which may look a logo, into the main audio-visual content.This watermark server may insert the logo of a content provider at theupper-left or upper-right of each frame in the main audio-visual contentas a watermark.

Additionally, the content recognizing service providing server 20 may bea watermark server that edits the main audio-visual content to insertcontent information into the main audio-visual content as an invisiblewatermark.

Additionally, the content recognizing service providing server 20 may bea fingerprint server that extracts feature information from some framesor audio samples of the main audio-visual content and stores it. Thisfeature information is called signature.

The multichannel video distributing server 30 receives and multiplexesbroadcast signals from a plurality of broadcasting stations and providesthe multiplexed broadcast signals to the broadcast receiving device 60.Especially, the multichannel video distributing server 30 performsdemodulation and channel decoding on the received broadcast signals toextract main audio-visual content and enhanced service, and then,performs channel encoding on the extracted main audio-visual content andenhanced service to generate a multiplexed signal for distribution. Atthis point, since the multichannel video distributing server 30 mayexclude the extracted enhanced service or may add another enhancedservice, a broadcasting station may not provide services led by it.There may be at least one multichannel video distributing server.

The broadcasting device 60 may tune a channel selected by a user andreceives a signal of the tuned channel, and then, performs demodulationand channel decoding on the received signal to extract a mainaudio-visual content. The broadcasting device 60 decodes the extractedmain audio-visual content through H.264/Moving Picture Experts Group-4advanced video coding (MPEG-4 AVC), Dolby AC-3 or Moving Picture ExpertsGroup-2 Advanced Audio Coding (MPEG-2 AAC) algorithm to generate anuncompressed main audio-visual (AV) content. The broadcast receivingdevice 60 provides the generated uncompressed main AV content to thevideo display device 100 through its external input port.

The enhanced service information providing server 40 provides enhancedservice information on at least one available enhanced service relatingto a main AV content in response to a request of a video display device.There may be at least one enhanced service providing server. Theenhanced service information providing server 40 may provide enhancedservice information on the enhanced service having the highest priorityamong a plurality of available enhanced services.

The enhanced service providing server 50 provides at least one availableenhanced service relating to a main AV content in response to a requestof a video display device. There may be at least one enhanced serviceproviding server.

The video display device 100 may be a television, a notebook computer, ahand phone, and a smart phone, each including a display unit. The videodisplay device 100 may receive an uncompressed main AV content from thebroadcast receiving device 60 or a broadcast signal including an encodedmain AV content from the contents providing server 10 or themultichannel video distributing server 30. The video display device 100may receive a content recognizing service from the content recognizingservice providing server 20 through the network 70, an address of atleast one available enhanced service relating to a main AV content fromthe enhanced service information providing server 40 through the network70, and at least one available enhanced service relating to a main AVcontent from the enhanced service providing server 50.

At least two of the content providing server 10, the content recognizingservice providing server 20, the multichannel video distributing server30, the enhanced service information providing server 40, and theplurality of enhanced service providing servers 50 may be combined in aform of one server and may be operated by one provider.

FIG. 31 is a block diagram illustrating a watermark based networktopology according to an embodiment.

As shown in FIG. 31, the watermark based network topology may furtherinclude a watermark server 21.

As shown in FIG. 31, the watermark server 21 edits a main AV content toinsert content information into it. The multichannel video distributingserver 30 may receive and distribute a broadcast signal including themodified main AV content. Especially, a watermark server may use adigital watermarking technique described below.

A digital watermark is a process for inserting information, which may bealmost undeletable, into a digital signal. For example, the digitalsignal may be audio, picture, or video. If the digital signal is copied,the inserted information is included in the copy. One digital signal maycarry several different watermarks simultaneously.

In visible watermarking, the inserted information may be identifiable ina picture or video. Typically, the inserted information may be a text orlogo identifying a media owner. If a television broadcasting stationadds its logo in a corner of a video, this is an identifiable watermark.

In invisible watermarking, although information as digital data is addedto audio, picture, or video, a user may be aware of a predeterminedamount of information but may not recognize it. A secret message may bedelivered through the invisible watermarking.

One application of the watermarking is a copyright protection system forpreventing the illegal copy of digital media. For example, a copy deviceobtains a watermark from digital media before copying the digital mediaand determines whether to copy or not on the bases of the content of thewatermark.

Another application of the watermarking is source tracking of digitalmedia. A watermark is embedded in the digital media at each point of adistribution path. If such digital media is found later, a watermark maybe extracted from the digital media and a distribution source may berecognized from the content of the watermark.

Another application of invisible watermarking is a description fordigital media.

A file format for digital media may include additional informationcalled metadata and a digital watermark is distinguished from metadatain that it is delivered as an AV signal itself of digital media.

The watermarking method may include spread spectrum, quantization, andamplitude modulation.

If a marked signal is obtained through additional editing, thewatermarking method corresponds to the spread spectrum. Although it isknown that the spread spectrum watermark is quite strong, not muchinformation is contained because the watermark interferes with anembedded host signal.

If a marked signal is obtained through the quantization, thewatermarking method corresponds to a quantization type. The quantizationwatermark is weak, much information may be contained.

If a marked signal is obtained through an additional editing methodsimilar to the spread spectrum in a spatial domain, a watermarkingmethod corresponds to the amplitude modulation.

FIG. 32 is a ladder diagram illustrating a data flow in a watermarkbased network topology according to an embodiment.

First, the content providing server 10 transmits a broadcast signalincluding a main AV content and an enhanced service in operation S101.

The watermark server 21 receives a broadcast signal that the contentproviding server 10 provides, inserts a visible watermark such as a logoor watermark information as an invisible watermark into the main AVcontent by editing the main AV content, and provides the watermarkedmain AV content and enhanced service to the MVPD 30 in operation S103.

The watermark information inserted through an invisible watermark mayinclude at least one of a watermark purpose, content information,enhanced service information, and an available enhanced service. Thewatermark purpose represents one of illegal copy prevention, viewerratings, and enhanced service acquisition.

The content information may include at least one of identificationinformation of a content provider that provides main AV content, main AVcontent identification information, time information of a contentsection used in content information acquisition, names of channelsthrough which main AV content is broadcasted, logos of channels throughwhich main AV content is broadcasted, descriptions of channels throughwhich main AV content is broadcasted, a usage information reportingperiod, the minimum usage time for usage information acquisition, andavailable enhanced service information relating to main AV content.

If the video display device 100 uses a watermark to acquire contentinformation, the time information of a content section used for contentinformation acquisition may be the time information of a content sectioninto which a watermark used is embedded. If the video display device 100uses a fingerprint to acquire content information, the time informationof a content section used for content information acquisition may be thetime information of a content section where feature information isextracted. The time information of a content section used for contentinformation acquisition may include at least one of the start time of acontent section used for content information acquisition, the durationof a content section used for content information acquisition, and theend time of a content section used for content information acquisition.

The usage information reporting address may include at least one of amain AV content watching information reporting address and an enhancedservice usage information reporting address. The usage informationreporting period may include at least one of a main AV content watchinginformation reporting period and an enhanced service usage informationreporting period. A minimum usage time for usage information acquisitionmay include at least one of a minimum watching time for a main AVcontent watching information acquisition and a minimum usage time forenhanced service usage information extraction.

On the basis that a main AV content is watched for more than the minimumwatching time, the video display device 100 acquires watchinginformation of the main AV content and reports the acquired watchinginformation to the main AV content watching information reportingaddress in the main AV content watching information reporting period.

On the basis that an enhanced service is used for more than the minimumusage time, the video display device 100 acquires enhanced service usageinformation and reports the acquired usage information to the enhancedservice usage information reporting address in the enhanced serviceusage information reporting period.

The enhanced service information may include at least one of informationon whether an enhanced service exists, an enhanced service addressproviding server address, an acquisition path of each available enhancedservice, an address for each available enhanced service, a start time ofeach available enhanced service, an end time of each available enhancedservice, a lifetime of each available enhanced service, an acquisitionmode of each available enhanced service, a request period of eachavailable enhanced service, priority information each available enhancedservice, description of each available enhanced service, a category ofeach available enhanced service, a usage information reporting address,a usage information reporting period, and the minimum usage time forusage information acquisition.

The acquisition path of available enhanced service may be representedwith IP or Advanced Television Systems Committee-Mobile/Handheld (ATSCM/H). If the acquisition path of available enhanced service is ATSC M/H,enhanced service information may further include frequency informationand channel information. An acquisition mode of each available enhancedservice may represent Push or Pull.

Moreover, the watermark server 21 may insert watermark information as aninvisible watermark into the logo of a main AV content.

For example, the watermark server 21 may insert a barcode at apredetermined position of a logo. At this point, the predeterminedposition of the logo may correspond to the first line at the bottom ofan area where the logo is displayed. The video display device 100 maynot display a barcode when receiving a main AV content including a logowith the barcode inserted.

For example, the watermark server 21 may insert a barcode at apredetermined position of a logo. At this point, the log may maintainits form.

For example, the watermark server 21 may insert N-bit watermarkinformation at each of the logos of M frames. That is, the watermarkserver 21 may insert M*N watermark information in M frames.

The MVPD 30 receives broadcast signals including watermarked main AVcontent and enhanced service and generates a multiplexed signal toprovide it to the broadcast receiving device 60 in operation S105. Atthis point, the multiplexed signal may exclude the received enhancedservice or may include new enhanced service.

The broadcast receiving device 60 tunes a channel that a user selectsand receives signals of the tuned channel, demodulates the receivedsignals, performs channel decoding and AV decoding on the demodulatedsignals to generate an uncompressed main AV content, and then, providesthe generated uncompressed main AV content to the video display device100 in operation S106.

Moreover, the content providing server 10 also broadcasts a broadcastsignal including a main AV content through a wireless channel inoperation S107.

Additionally, the MVPD 30 may directly transmit a broadcast signalincluding a main AV content to the video display device 100 withoutgoing through the broadcast receiving device 60 in operation S108.

The video display device 100 may receive an uncompressed main AV contentthrough the broadcast receiving device 60. Additionally, the videodisplay device 100 may receive a broadcast signal through a wirelesschannel, and then, may demodulate and decode the received broadcastsignal to obtain a main AV content. Additionally, the video displaydevice 100 may receive a broadcast signal from the MVPD 30, and then,may demodulate and decode the received broadcast signal to obtain a mainAV content. The video display device 100 extracts watermark informationfrom some frames or a section of audio samples of the obtained main AVcontent. If watermark information corresponds to a logo, the videodisplay device 100 confirms a watermark server address corresponding toa logo extracted from a corresponding relationship between a pluralityof logos and a plurality of watermark server addresses. When thewatermark information corresponds to the logo, the video display device100 cannot identify the main AV content only with the logo.Additionally, when the watermark information does not include contentinformation, the video display device 100 cannot identify the main AVcontent but the watermark information may include content provideridentifying information or a watermark server address. When thewatermark information includes the content provider identifyinginformation, the video display device 100 may confirm a watermark serveraddress corresponding to the content provider identifying informationextracted from a corresponding relationship between a plurality ofcontent provider identifying information and a plurality of watermarkserver addresses. In this manner, when the video display device 100cannot identify a main AV content the video display device 100 only withthe watermark information, it accesses the watermark server 21corresponding to the obtained watermark server address to transmit afirst query in operation S109.

The watermark server 21 provides a first reply to the first query inoperation S111. The first reply may include at least one of contentinformation, enhanced service information, and an available enhancedservice.

If the watermark information and the first reply do not include anenhanced service address, the video display device 100 cannot obtainenhanced service. However, the watermark information and the first replymay include an enhanced service address providing server address. Inthis manner, the video display device 100 does not obtain a serviceaddress or enhanced service through the watermark information and thefirst reply. If the video display device 100 obtains an enhanced serviceaddress providing server address, it accesses the enhanced serviceinformation providing server 40 corresponding to the obtained enhancedservice address providing server address to transmit a second queryincluding content information in operation S119.

The enhanced service information providing server 40 searches at leastone available enhanced service relating to the content information ofthe second query. Later, the enhanced service information providingserver 40 provides to the video display device 100 enhanced serviceinformation for at least one available enhanced service as a secondreply to the second query in operation S121.

If the video display device 100 obtains at least one available enhancedservice address through the watermark information, the first reply, orthe second reply, it accesses the at least one available enhancedservice address to request enhanced service in operation S123, and then,obtains the enhanced service in operation S125.

FIG. 33 is a view illustrating a watermark based content recognitiontiming according to an embodiment.

As shown in FIG. 33, when the broadcast receiving device 60 is turned onand tunes a channel, and also, the video display device 100 receives amain AV content of the turned channel from the broadcast receivingdevice 60 through an external input port 111, the video display device100 may sense a content provider identifier (or a broadcasting stationidentifier) from the watermark of the main AV content. Then, the videodisplay device 100 may sense content information from the watermark ofthe main AV content on the basis of the sensed content provideridentifier.

At this point, as shown in FIG. 33, the detection available period ofthe content provider identifier may be different from that of thecontent information. Especially, the detection available period of thecontent provider identifier may be shorter than that of the contentinformation. Through this, the video display device 100 may have anefficient configuration for detecting only necessary information.

FIG. 34 is a block diagram illustrating a fingerprint based networktopology according to an embodiment.

As shown in FIG. 34, the network topology may further include afingerprint server 22.

As shown in FIG. 34, the fingerprint server 22 does not edit a main AVcontent, but extracts feature information from some frames or a sectionof audio samples of the main AV content and stores the extracted featureinformation. Then, when receiving the feature information from the videodisplay device 100, the fingerprint server 22 provides an identifier andtime information of an AV content corresponding to the received featureinformation.

FIG. 35 is a ladder diagram illustrating a data flow in a fingerprintbased network topology according to an embodiment.

First, the content providing server 10 transmits a broadcast signalincluding a main AV content and an enhanced service in operation S201.

The fingerprint server 22 receives a broadcast signal that the contentproviding server 10, extracts a plurality of pieces of featureinformation from a plurality of frame sections or a plurality of audiosections of the main AV content, and establishes a database for aplurality of query results corresponding to the plurality of featureinformation in operation S203. The query result may include at least oneof content information, enhanced service information, and an availableenhanced service.

The MVPD 30 receives broadcast signals including a main AV content andenhanced service and generates a multiplexed signal to provide it to thebroadcast receiving device 60 in operation S205. At this point, themultiplexed signal may exclude the received enhanced service or mayinclude new enhanced service.

The broadcast receiving device 60 tunes a channel that a user selectsand receives signals of the tuned channel, demodulates the receivedsignals, performs channel decoding and AV decoding on the demodulatedsignals to generate an uncompressed main AV content, and then, providesthe generated uncompressed main AV content to the video display device100 in operation S206.

Moreover, the content providing server 10 also broadcasts a broadcastsignal including a main AV content through a wireless channel inoperation S207.

Additionally, the MVPD 30 may directly transmit a broadcast signalincluding a main AV content to the video display device 100 withoutgoing through the broadcast receiving device 60.

The video display device 100 may receive an uncompressed main AV contentthrough the broadcast receiving device 60. Additionally, the videodisplay device 100 may receive a broadcast signal through a wirelesschannel, and then, may demodulate and decode the received broadcastsignal to obtain a main AV content. Additionally, the video displaydevice 100 may receive a broadcast signal from the MVPD 30, and then,may demodulate and decode the received broadcast signal to obtain a mainAV content. The video display device 100 extracts feature informationfrom some frames or a section of audio samples of the obtained main AVcontent in operation S213.

The video display device 100 accesses the fingerprint server 22corresponding to the predetermined fingerprint server address totransmit a first query including the extracted feature information inoperation S215.

The fingerprint server 22 provides a query result as a first reply tothe first query in operation S217. If the first reply corresponds tofail, the video display device 100 accesses the fingerprint server 22corresponding to another fingerprint server address to transmit a firstquery including the extracted feature information.

The fingerprint server 22 may provide Extensible Markup Language (XML)document as a query result. Examples of the XML document containing aquery result will be described.

FIG. 36 is a view illustrating an XML schema diagram of ACR-Resulttypecontaining a query result according to an embodiment.

As shown in FIG. 36, ACR-Resulttype containing a query result includesResultCode attributes and ContentID, NTPTimestamp,SignalingChannelInformation, and ServiceInformation elements.

For example, if the ResultCode attribute has 200, this may mean that thequery result is successful. For example, if the ResultCode attribute has404, this may mean that the query result is unsuccessful.

The SignalingChannelInformation element includes a SignalingChannelURL,and the SignalingChannelURL element includes an UpdateMode andPollingCycle attributes. The UpdateMode attribute may have a Pull valueor a Push value.

The ServiceInformation element includes ServiceName, ServiceLogo, andServiceDescription elements.

An XML schema of ACR-ResultType containing the query result isillustrated below.

TABLE 34 <xs:complexType name=“ACR-ResultType”>   <xs:sequence>   <xs:element name=“ContentID” type=“xs:anyURI”/>    <xs:elementname=“NTPTimestamp” type=“xs:unsignedLong”/>    <xs:elementname=“SignalingChannelInformation”>     <xs:complexType>     <xs:sequence>       <xs:element name=“SignalingChannelURL”      maxOccurs=“unbounded”>        <xs:complexType>        <xs:simpleContent>          <xs:extension base=“xs:anyURI”>          <xs:attribute name=“UpdateMode”>            <xs:simpleType>            <xs:restriction base=“xs:string”>             <xs:enumeration value=“Pull”/>              <xs:enumerationvalue=“Push”/>             </xs:restriction>            </xs:simpleType>          </xs:attribute>           <xs:attribute name=“PollingCycle”          type=“xs:unsignedInt”/>          </xs:extension>        </xs:simpleContent>        </xs:complexType>       </xs:element>     </xs:sequence>     </xs:complexType>    </xs:element>   <xs:element name=“ServiceInformation”>     <xs:complexType>     <xs:sequence>       <xs:element name=“ServiceName”type=“xs:string”/>       <xs:element name=“ServiceLogo” type=“xs:anyURI”      minOccurs=“0”/>       <xs:element name=“ServiceDescription”type=“xs:string”       minOccurs=“0” maxOccurs=“unbounded”/>     </xs:sequence>     </xs:complexType>    </xs:element>    <xs:anynamespace=“##other” processContents=“skip”    minOccurs=“0”maxOccurs=“unbounded”/>   </xs:sequence>   <xs:attributename=“ResultCode” type=“xs:string” use=“required”/>   <xs:anyAttributeprocessContents=“skip”/>  </xs:complexType>

As the ContentID element, an ATSC content identifier may be used asshown in table below.

TABLE 35 Syntax The Number of bits format ATSC_content_identifier(){ 16uimsbf  TSID  reserved 2 bslbf  end_of_day 5 uimsbf  unique_for 9 uimsbf content_id var }

As shown in the table, the ATSC content identifier has a structureincluding TSID and a house number.

The 16 bit unsigned integer TSID carries a transport stream identifier.

The 5 bit unsigned integer end_of_day is set with an hour in a day ofwhen a content_id value can be reused after broadcasting is finished.

The 9 bit unsigned integer unique_for is set with the number of day ofwhen the content_id value cannot be reused.

Content_id represents a content identifier. The video display device 100reduces unique_for by 1 in a corresponding time to end_of_day daily andpresumes that content_id is unique if unique_for is not 0.

Moreover, as the ContentID element, a global service identifier forATSC-M/H service may be used as described below.

The global service identifier has the following form.

-   -   urn:oma:bcast:iauth:atsc:service:<region>:<xsid>:<serviceid>.

Here, <region> is an international country code including two charactersregulated by ISO 639-2. <xsid> for local service is a decimal number ofTSID as defined in <region>, and <xsid> (regional service) (major>69) is“0”. <serviceid> is defined with <major> or <minor>. <major> represent aMajor Channel number, and <minor> represents a Minor Channel Number.

Examples of the global service identifier are as follows.

-   -   urn:oma:bcast:iauth:atsc:service:us:1234:5.1.    -   urn:oma:bcastiauth:atsc:service:us:0:100.200.

Moreover, as the ContentID element, an ATSC content identifier may beused as described below.

The ATSC content identifier has the following form.

urn:oma:bcast:iauth:atsc:content:<region>:<xsidz>:<contentid>:<unique_for>:<end_of_day>.

Here, <region> is an international country code including two charactersregulated by ISO 639-2. <xsid> for local service is a decimal number ofTSID as defined in <region>, and may be followed by “.”<serviceid>.<xsid> for (regional service) (major>69) is <serviceid>. <content_id> isa base64 sign of a content_id field defined in above described table,<unique_for> is a decimal number sign of an unique_for field defined inabove described table, and <end_of_day> is a decimal number sign of anend_of_day field defined in above described table.

Hereinafter, FIG. 35 is described again.

If the query result does not include an enhanced service address orenhanced service but includes an enhanced service address providingserver address, the video display device 100 accesses the enhancedservice information providing server 40 corresponding to the obtainedenhanced service address providing server address to transmit a secondquery including content information in operation S219.

The enhanced service information providing server 40 searches at leastone available enhanced service relating to the content information ofthe second query. Later, the enhanced service information providingserver 40 provides to the video display device 100 enhanced serviceinformation for at least one available enhanced service as a secondreply to the second query in operation S221.

If the video display device 100 obtains at least one available enhancedservice address through the first reply or the second reply, it accessesthe at least one available enhanced service address to request enhancedservice in operation S223, and then, obtains the enhanced service inoperation S225.

When the UpdateMode attribute has a Pull value, the video display device100 transmits an HTTP request to the enhanced service providing server50 through SignalingChannelURL and receives an HTTP reply including aPSIP binary stream from the enhanced service providing server 50 inresponse to the request. In this case, the video display device 100 maytransmit the HTTP request according to a Polling period designated asthe PollingCycle attribute. Additionally, the SignalingChannelURLelement may have an update time attribute. In this case, the videodisplay device 100 may transmit the HTTP request according to an updatetime designated as the update time attribute.

If the UpdateMode attribute has a Push value, the video display device100 may receive update from a server asynchronously throughXMLHTTPRequest API. After the video display device 100 transmits anasynchronous request to a server through XMLHTTPRequest object, if thereis a change of signaling information, the server provides the signalinginformation as a reply through the channel. If there is limitation insession standby time, a server generates a session timeout reply and areceiver recognizes the generated timeout reply to transmit a requestagain, so that a signaling channel between the receiver and the servermay be maintained for all time.

FIG. 37 is a block diagram illustrating a watermark and fingerprintbased network topology according to an embodiment.

As shown in FIG. 37, the watermark and fingerprint based networktopology may further include a watermark server 21 and a fingerprintserver 22.

As shown in FIG. 37, the watermark server 21 inserts content provideridentifying information into a main AV content. The watermark server 21may insert content provider identifying information as a visiblewatermark such as a logo or an invisible watermark into a main AVcontent.

The fingerprint server 22 does not edit a main AV content, but extractsfeature information from some frames or a certain section of audiosamples of the main AV content and stores the extracted featureinformation. Then, when receiving the feature information from the videodisplay device 100, the fingerprint server 22 provides an identifier andtime information of an AV content corresponding to the received featureinformation.

FIG. 38 is a ladder diagram illustrating a data flow in a watermark andfingerprint based network topology according to an embodiment.

First, the content providing server 10 transmits a broadcast signalincluding a main AV content and an enhanced service in operation S301.

The watermark server 21 receives a broadcast signal that the contentproviding server 10 provides, inserts a visible watermark such as a logoor watermark information as an invisible watermark into the main AVcontent by editing the main AV content, and provides the watermarkedmain AV content and enhanced service to the MVPD 30 in operation S303.The watermark information inserted through an invisible watermark mayinclude at least one of content information, enhanced serviceinformation, and an available enhanced service. The content informationand enhanced service information are described above.

The MVPD 30 receives broadcast signals including watermarked main AVcontent and enhanced service and generates a multiplexed signal toprovide it to the broadcast receiving device 60 in operation S305. Atthis point, the multiplexed signal may exclude the received enhancedservice or may include new enhanced service.

The broadcast receiving device 60 tunes a channel that a user selectsand receives signals of the tuned channel, demodulates the receivedsignals, performs channel decoding and AV decoding on the demodulatedsignals to generate an uncompressed main AV content, and then, providesthe generated uncompressed main AV content to the video display device100 in operation S306.

Moreover, the content providing server 10 also broadcasts a broadcastsignal including a main AV content through a wireless channel inoperation S307.

Additionally, the MVPD 30 may directly transmit a broadcast signalincluding a main AV content to the video display device 100 withoutgoing through the broadcast receiving device 60 in operation S308.

The video display device 100 may receive an uncompressed main AV contentthrough the broadcast receiving device 60. Additionally, the videodisplay device 100 may receive a broadcast signal through a wirelesschannel, and then, may demodulate and decode the received broadcastsignal to obtain a main AV content. Additionally, the video displaydevice 100 may receive a broadcast signal from the MVPD 30, and then,may demodulate and decode the received broadcast signal to obtain a mainAV content. The video display device 100 extracts watermark informationfrom audio samples in some frames or periods of the obtained main AVcontent. If watermark information corresponds to a logo, the videodisplay device 100 confirms a watermark server address corresponding toa logo extracted from a corresponding relationship between a pluralityof logos and a plurality of watermark server addresses. When thewatermark information corresponds to the logo, the video display device100 cannot identify the main AV content only with the logo.Additionally, when the watermark information does not include contentinformation, the video display device 100 cannot identify the main AVcontent but the watermark information may include content provideridentifying information or a watermark server address. When thewatermark information includes the content provider identifyinginformation, the video display device 100 may confirm a watermark serveraddress corresponding to the content provider identifying informationextracted from a corresponding relationship between a plurality ofcontent provider identifying information and a plurality of watermarkserver addresses. In this manner, when the video display device 100cannot identify a main AV content the video display device 100 only withthe watermark information, it accesses the watermark server 21corresponding to the obtained watermark server address to transmit afirst query in operation S309.

The watermark server 21 provides a first reply to the first query inoperation S311. The first reply may include at least one of afingerprint server address, content information, enhanced serviceinformation, and an available enhanced service. The content informationand enhanced service information are described above.

If the watermark information and the first reply include a fingerprintserver address, the video display device 100 extracts featureinformation from some frames or a certain section of audio samples ofthe main AV content in operation S313.

The video display device 100 accesses the fingerprint server 22corresponding to the fingerprint server address in the first reply totransmit a second query including the extracted feature information inoperation S315.

The fingerprint server 22 provides a query result as a second reply tothe second query in operation S317.

If the query result does not include an enhanced service address orenhanced service but includes an enhanced service address providingserver address, the video display device 100 accesses the enhancedservice information providing server 40 corresponding to the obtainedenhanced service address providing server address to transmit a thirdquery including content information in operation S319.

The enhanced service information providing server 40 searches at leastone available enhanced service relating to the content information ofthe third query. Later, the enhanced service information providingserver 40 provides to the video display device 100 enhanced serviceinformation for at least one available enhanced service as a third replyto the third query in operation S321.

If the video display device 100 obtains at least one available enhancedservice address through the first reply, the second reply, or the thirdreply, it accesses the at least one available enhanced service addressto request enhanced service in operation S323, and then, obtains theenhanced service in operation S325.

Then, referring to FIG. 39, the video display device 100 will bedescribed according to an embodiment.

FIG. 39 is a block diagram illustrating the video display deviceaccording to the embodiment.

As shown in FIG. 39, the video display device 100 includes a broadcastsignal receiving unit 101, a demodulation unit 103, a channel decodingunit 105, a demultiplexing unit 107, an AV decoding unit 109, anexternal input port 111, a play controlling unit 113, a play device 120,an enhanced service management unit 130, a data transmitting/receivingunit 141, and a memory 150.

The broadcast signal receiving unit 101 receives a broadcast signal fromthe content providing server 10 or MVPD 30.

The demodulation unit 103 demodulates the received broadcast signal togenerate a demodulated signal.

The channel decoding unit 105 performs channel decoding on thedemodulated signal to generate channel-decoded data.

The demultiplexing unit 107 separates a main AV content and enhancedservice from the channel-decoded data. The separated enhanced service isstored in an enhanced service storage unit 152.

The AV decoding unit 109 performs AV decoding on the separated main AVcontent to generate an uncompressed main AV content.

Moreover, the external input port 111 receives an uncompressed main AVcontent from the broadcast receiving device 60, a digital versatile disk(DVD) player, a Blu-ray disk player, and so on. The external input port111 may include at least one of a DSUB port, a High DefinitionMultimedia Interface (HDMI) port, a Digital Visual Interface (DVI) port,a composite port, a component port, and an S-Video port.

The play controlling unit 113 controls the play device 120 to play atleast one of an uncompressed main AV content that the AV decoding unit109 generates and an uncompressed main AV content received from theexternal input port 111 according to a user's selection.

The play device 120 includes a display unit 121 and a speaker 123. Thedisplay unit 21 may include at least one of a liquid crystal display(LCD), a thin film transistor-liquid crystal display (TFT LCD), anorganic light-emitting diode (OLED), a flexible display, and a 3Ddisplay.

The enhanced service management unit 130 obtains content information ofthe main AV content and obtains available enhanced service on the basisof the obtained content information. Especially, as described above, theenhanced service management unit 130 may obtain the identificationinformation of the main AV content on the basis of some frames or acertain section of audio samples the uncompressed main AV content. Thisis called automatic contents recognition (ACR) in this specification.

The data transmitting/receiving unit 141 may include an AdvancedTelevision Systems Committee-Mobile/Handheld (ATSC-M/H) channeltransmitting/receiving unit 141 a and an IP transmitting/receiving unit141 b.

The memory 150 may include at least one type of storage medium such as aflash memory type, a hard disk type, a multimedia card micro type, acard type memory such as SD or XD memory, Random Access Memory (RAM),Static Random Access Memory (SRAM), Read-Only Memory (ROM), ElectricallyErasable Programmable Read-Only Memory (EEPROM), Programmable Read-OnlyMemory (PROM), magnetic memory, magnetic disk, and optical disk. Thevideo display device 100 may operate in linkage with a web storageperforming a storage function of the memory 150 in the Internet.

The memory 150 may include a content information storage unit 151, anenhanced service storage unit 152, a logo storage unit 153, a settinginformation storage unit 154, a bookmark storage unit 155, a userinformation storage unit 156, and a usage information storage unit 157.

The content information storage unit 151 stores a plurality of contentinformation corresponding to a plurality of feature information.

The enhanced service storage unit 152 may store a plurality of enhancedservices corresponding to a plurality of feature information or aplurality of enhanced services corresponding to a plurality of contentinformation.

The logo storage unit 153 stores a plurality of logos. Additionally, thelogo storage unit 153 may further store content provider identifierscorresponding to the plurality of logos or watermark server addressescorresponding to the plurality of logos.

The setting information storage unit 154 stores setting information forACR.

The bookmark storage unit 155 stores a plurality of bookmarks.

The user information storage unit 156 stores user information. The userinformation may include at least one of at least one account informationfor at least one service, regional information, family memberinformation, preferred genre information, video display deviceinformation, and a usage information range. The at least one accountinformation may include account information for a usage informationmeasuring server and account information of social network service suchas Twitter and Facebook. The regional information may include addressinformation and zip codes. The family member information may include thenumber of family members, each member's age, each member's sex, eachmember's religion, and each member's job. The preferred genreinformation may be set with at least one of sports, movie, drama,education, news, entertainment, and other genres. The video displaydevice information may include information such as the type,manufacturer, firmware version, resolution, model, OS, browser, storagedevice availability, storage device capacity, and network speed of avideo display device. Once the usage information range is set, the videodisplay device 100 collects and reports main AV content watchinginformation and enhanced service usage information within the set range.The usage information range may be set in each virtual channel.Additionally, the usage information measurement allowable range may beset over an entire physical channel.

The usage information providing unit 157 stores the main AV contentwatching information and the enhanced service usage information, whichare collected by the video display device 100. Additionally, the videodisplay device 100 analyzes a service usage pattern on the basis of thecollected main AV content watching information and enhanced serviceusage information, and stores the analyzed service usage pattern in theusage information storage unit 157.

The enhanced service management unit 130 may obtain the contentinformation of the main AV content from the fingerprint server 22 or thecontent information storage unit 151. If there is no content informationor sufficient content information, which corresponds to the extractedfeature information, in the content information storage unit 151, theenhanced service management unit 130 may receive additional contentinformation through the data transmitting/receiving unit 141. Moreover,the enhanced service management unit 130 may update the contentinformation continuously.

The enhanced service management unit 130 may obtain available enhancedservice from the enhanced service providing server 50 or the enhancedservice storage unit 153. If there is no enhanced service or sufficientenhanced service in the enhanced service storage unit 153, the enhancedservice management unit 130 may update enhanced service through the datatransmitting/receiving unit 141. Moreover, the enhanced servicemanagement unit 130 may update the enhanced service continuously.

The enhanced service management unit 130 may extracts a logo from themain AV content, and then, may make a query to the logo storage unit 155to obtain a content provider identifier or watermark server address,which is corresponds to the extracted logo. If there is no logo or asufficient logo, which corresponds to the extracted logo, in the logostorage unit 155, the enhanced service management unit 130 may receivean additional logo through the data transmitting/receiving unit 141.Moreover, the enhanced service management unit 130 may update the logocontinuously.

The enhanced service management unit 130 may compare the logo extractedfrom the main AV content with the plurality of logos in the logo storageunit 155 through various methods. The various methods may reduce theload of the comparison operation.

For example, the enhanced service management unit 130 may perform thecomparison on the basis of color characteristics. That is, the enhancedservice management unit 130 may compare the color characteristic of theextracted logo with the color characteristics of the logos in the logostorage unit 155 to determine whether they are identical or not.

Moreover, the enhanced service management unit 130 may perform thecomparison on the basis of character recognition. That is, the enhancedservice management unit 130 may compare the character recognized fromthe extracted logo with the characters recognized from the logos in thelogo storage unit 155 to determine whether they are identical or not.

Furthermore, the enhanced service management unit 130 may perform thecomparison on the basis of the contour of the logo. That is, theenhanced service management unit 130 may compare the contour of theextracted logo with the contours of the logos in the logo storage unit155 to determine whether they are identical or not.

Then, referring to FIGS. 40 and 41, a method of synchronizing a playbacktime of a main AV content with a playback time of an enhanced serviceaccording to an embodiment will be described.

FIG. 40 is a flowchart illustrating a method of synchronizing a playbacktime of a main AV content with a playback time of an enhanced serviceaccording to an embodiment.

Enhanced service information may include a start time of an enhancedservice. At this point, the video display device 100 may need to startthe enhanced service at the start time. However, since the video displaydevice 100 receives a signal transmitting an uncompressed main AVcontent with no time stamp, the reference time of a plying time of themain AV content is different from that of a start time of the enhancedservice. Although the video display device 100 receives a main AVcontent having time information, the reference time of a plying time ofthe main AV content may be different from that of a start time of theenhanced service, like rebroadcasting. Accordingly, the video displaydevice 100 may need to synchronize the reference time of the main AVcontent with that of the enhanced service. Especially, the video displaydevice 100 may need to synchronize the playback time of the main AVcontent with the start time of the enhanced service.

First, the enhanced service management unit 130 extracts a certainsection of a main AV content in operation S801. The section of the mainAV content may include at least one of some video frames or a certainaudio section of the main AV content. Time that the enhanced servicemanagement unit 130 extracts the section of the main AV content isdesignated as Tn.

The enhanced service management unit 130 obtains content information ofa main AV content on the basis of the extracted section S803. In moredetail, the enhanced service management unit 130 decodes informationencoded with invisible watermark in the extracted section to obtaincontent information. Additionally, the enhanced service management unit130 may extract feature information in the extracted section, and obtainthe content information of the main AV content from the fingerprintserver 22 or the content information storage unit 151 on the basis ofthe extracted feature information. Time that the enhanced servicemanagement unit 130 obtains the content information is designated as Tm.

Moreover, the content information includes a start time Ts of theextracted section. After the content information acquisition time Tm,the enhanced service management unit 130 synchronizes the playback timeof the main AV content with the start time of the enhanced service onthe biases of Ts, Tm, and Tn S805. In more detail, the enhanced servicemanagement unit 130 regards the content information acquisition time Tmas a time Tp, which can be calculated by Tp=Ts+(Tm−Tn).

Additionally, the enhanced service management unit 130 regards a time ofwhen Tx elapses after the content information acquisition time as Tp+Tx.

Then, the enhanced service management unit 130 obtains an enhancedservice and its start time Ta on the obtained content information inoperation S807.

If the synchronized playback time of the main AV content is identical tothe start time Ta of the enhanced service, the enhanced servicemanagement unit 130 starts the obtained enhanced service in operationS809. In more detail, the enhanced service management unit 130 may startthe enhanced service when Tp+Tx=Ta is satisfied.

FIG. 41 is a conceptual diagram illustrating a method of synchronizing aplayback time of a main AV content with a playback time of an enhancedservice according to an embodiment.

As shown in FIG. 41, the video display device 100 extracts an AV sampleduring a system time Tn.

The video display device 100 extracts feature information from theextracted AV sample, and transmits a query including the extractedfeature information to the fingerprint server 22 to receive a queryresult. The video display device 100 confirms whether a start time Ts ofthe extracted AV sample corresponds to 11000 ms at Tm by parsing thequery result.

Accordingly, the video display device 100 regards the time of when thestart time of the extracted AV sample is confirmed as Ts+(Tm−Tn), sothat, after that, the playback time of the main AV content may besynchronized with the start time of the enhanced service.

Next, a structure of a video display device according to variousembodiments will be described with reference to FIGS. 42 and 43.

FIG. 42 is a block diagram illustrating a structure of a fingerprintbased video display device according to another embodiment.

As shown in FIG. 42 a tuner 501 extracts a symbol from an 8-VSB RFsignal transmitted through an air channel.

An 8-VSB demodulator 503 demodulates the 8-VSB symbol that the tuner 501extracts and restores meaningful digital data.

A VSB decoder 505 decodes the digital data that the 8-VSB demodulator503 to restore an ATSC main service and ATSC M/H service.

An MPEG-2 TP Demux 507 filters a Transport Packet that the video displaydevice 100 is to process from an MPEG-2 Transport Packet transmittedthrough an 8-VSB signal or an MPEG-2 Transport Packet stored in a PVRStorage to relay the filtered Transport Packet into a processing module.

A PES decoder 539 buffers and restores a Packetized Elementary Streamtransmitted through an MPEG-2 Transport Stream.

A PSI/PSIP decoder 541 buffers and analyzes PSI/PSIP Section Datatransmitted through an MPEG-2 Transport Stream. The analyzed PSI/PSIPdata are collected by a Service Manager (not shown), and then, is storedin DB in a form of Service Map and Guide data.

A DSMCC Section Buffer/Handler 511 buffers and processes DSMCC SectionData for file transmission through MPEG-2 TP and IP Datagramencapsulation.

An IP/UDP Datagram Buffer/Header Parser 513 buffers and restores IPDatagram, which is encapsulated through DSMCC Addressable section andtransmitted through MPEG-2 TP to analyze the Header of each Datagram.Additionally, an IP/UDP Datagram Buffer/Header Parser 513 buffers andrestores UDP Datagram transmitted through IP Datagram, and then analyzesand processes the restored UDP Header.

A Stream component handler 557 may include ES Buffer/Handler, PCRHandler, STC module, Descrambler, CA Stream Buffer/Handler, and ServiceSignaling Section Buffer/Handler.

The ES Buffer/Handler buffers and restores an Elementary Stream such asVideo and Audio data transmitted in a PES form to deliver it to a properA/V Decoder.

The PCR Handler processes Program Clock Reference (PCR) Data used forTime synchronization of Audio and Video Stream.

The STC module corrects Clock values of the A/V decoders by using aReference Clock value received through PCR Handler to perform TimeSynchronization.

When scrambling is applied to the received IP Datagram, the Descramblerrestores data of Payload by using Encryption key delivered from the CAStream Handler.

The CA Stream Buffer/Handler buffers and processes Data such as Keyvalues for Descrambling of EMM and ECM, which are transmitted for aConditional Access function through MPEG-2 TS or IP Stream. An output ofthe CA Stream Buffer/Handler is delivered to the Descrambler, and then,the descrambler descrambles MPEG-2 TP or IP Datagram, which carriers A/VData and File Data.

The Service Signaling Section Buffer/Handler buffers, restores, andanalyzes NRT Service Signaling Channel Section Data transmitted in aform of IP Datagram. The Service Manager (not shown) collects theanalyzed NRT Service Signaling Channel Section data and stores them inDB in a form of Service Map and Guide data.

The A/V Decoder 561 decodes the Audio/Video data received through an ESHandler to present them to a user.

An MPEG-2 Service Demux (not shown) may include an MPEG-2 TPBuffer/Parser, a Descrambler, and a PVR Storage module.

An MPEG-2 TP Buffer/Parser (not shown) buffers and restores an MPEG-2Transport Packet transmitted through an 8-VSB signal, and also detectsand processes a Transport Packet Header.

The Descrambler restores the data of Payload by using an Encryption key,which is delivered from the CA Stream Handler, on the Scramble appliedPacket payload in the MPEG-2 TP.

The PVR Storage module stores an MPEG-2 TP received through an 8-VSBsignal at the user's request and outputs an MPEG-2 TP at the user'srequest. The PVR storage module may be controlled by the PVR manager(not shown).

The File Handler 551 may include an ALC/LCT Buffer/Parser, an FDTHandler, an XML Parser, a File Reconstruction Buffer, a Decompressor, aFile Decoder, and a File Storage.

The ALC/LCT Buffer/Parser buffers and restores ALC/LCT data transmittedthrough a UDP/IP Stream, and analyzes a Header and Header extension ofALC/LCT. The ALC/LCT Buffer/Parser may be controlled by an NRT ServiceManager (not shown).

The FDT Handler analyzes and processes a File Description Table of FLUTEprotocol transmitted through an ALC/LCT session. The FDT Handler may becontrolled by an NRT Service Manager (not shown).

The XML Parser analyzes an XML Document transmitted through an ALC/LCTsession, and then, delivers the analyzed data to a proper module such asan FDT Handler and an SG Handler.

The File Reconstruction Buffer restores a file transmitted through anALC/LCT, FLUTE session.

If a file transmitted through an ALC/LCT and FLUTE session iscompressed, the Decompressor performs a process to decompress the file.

The File Decoder decodes a file restored in the File ReconstructionBuffer, a file decompressed in the decompressor, or a film extractedfrom the File Storage.

The File Storage stores or extracts a restored file if necessary.

The M/W Engine (not shown) processes data such as a file, which is notan A/V Stream transmitted through DSMCC Section and IP Datagram. The M/WEngine delivers the processed data to a Presentation Manager module.

The SG Handler (not shown) collects and analyzes Service Guide datatransmitted in an XML Document form, and then, delivers them to the EPGManager.

The Service Manager (not shown) collects and analyzes PSI/PSIP Datatransmitted through an MPEG-2 Transport Stream and Service SignalingSection Data transmitted through an IP Stream, so as to produce aService Map. The Service Manager (not shown) stores the produced servicemap in a Service Map & Guide Database, and controls an access to aService that a user wants. The Service Manager is controlled by theOperation Controller (not shown), and controls the Tuner 501, the MPEG-2TP Demux 507, and the IP Datagram Buffer/Handler 513.

The NRT Service Manager (not shown) performs an overall management onthe NRT service transmitted in an object/file form through a FLUTEsession. The NRT Service Manager (not shown) may control the FDT Handlerand File Storage.

The Application Manager (not shown) performs overall management onApplication data transmitted in a form of object and file.

The UI Manager (not shown) delivers a user input to an OperationController through a User Interface, and starts a process for a servicethat a user requests.

The Operation Controller (not shown) processes a command of a user,which is received through a UI Manager, and allows a Manager of anecessary module to perform a corresponding action.

The Fingerprint Extractor 565 extracts fingerprint feature informationfrom an AV stream.

The Fingerprint Comparator 567 compares the feature informationextracted by the Fingerprint Extractor with a Reference fingerprint tofind an identical content. The Fingerprint Comparator 567 may use aReference fingerprint DB stored in local and may query a Fingerprintquery server on the internet to receive a result. The matched resultdata obtained by a comparison result may be delivered to Application andused.

As an ACR function managing module or an application module providing anenhanced service on the basis of ACR, the Application 569 identifies abroadcast content in watching to provide an enhanced service related toit.

FIG. 43 is a block diagram illustrating a structure of a watermark basedvideo display device according to another embodiment.

Although the watermark based video display device of FIG. 43 is similarto the fingerprint based video display device of FIG. 42, thefingerprint based video display device does not includes the FingerprintExtractor 565 and the Fingerprint Comparator 567, but further includesthe Watermark Extractor 566.

The Watermark Extractor 566 extracts data inserted in a watermark formfrom an Audio/Video stream. The extracted data may be delivered to anApplication and may be used.

FIG. 44 is a diagram showing data which may be delivered via awatermarking scheme according to one embodiment of the presentinvention.

As described above, an object of ACR via a WM is to obtain supplementaryservice related information of content from incompressible audio/videoin an environment capable of accessing only incompressible audio/video(that is, an environment in which audio/video is received from acable/satellite/IPTV, etc.). Such an environment may be referred to asan ACR environment. In the ACR environment, since a receiver receivesincompressible audio/video data only, the receiver may not confirm whichcontent is currently being displayed. Accordingly, the receiver uses acontent source ID, a current point of time of a broadcast program andURL information of a related application delivered by a WM to identifydisplayed content and provide an interactive service.

In delivery of a supplementary service related to a broadcast programusing an audio/video watermark (WM), all supplementary information maybe delivered by the WM as a simplest method. In this case, allsupplementary information may be detected by a WM detector tosimultaneously process information detected by the receiver.

However, in this case, if the amount of WMs inserted into audio/videodata increases, total quality of audio/video may deteriorate. For thisreason, only minimum necessary data may be inserted into the WM. Astructure of WM data for enabling a receiver to efficiently receive andprocess a large amount of information while inserting minimum data as aWM needs to be defined. A data structure used for the WM may be equallyused even in a fingerprinting scheme which is relatively less influencedby the amount of data.

As shown, data delivered via the watermarking scheme according to oneembodiment of the present invention may include an ID of a contentsource, a timestamp, an interactive application URL, a timestamp's type,a URL protocol type, an application event, a destination type, etc. Inaddition, various types of data may be delivered via the WM schemeaccording to the present invention.

The present invention proposes the structure of data included in a WMwhen ACR is performed via a WM scheme. For shown data types, a mostefficient structure is proposed by the present invention.

Data which can be delivered via the watermarking scheme according to oneembodiment of the present invention include the ID of the contentsource. In an environment using a set top box, a receiver (a terminal orTV) may not check a program name, channel information, etc. when amultichannel video programming distributor (MVPD) does not deliverprogram related information via the set top box. Accordingly, a uniqueID for identifying a specific content source may be necessary. In thepresent invention, an ID type of a content source is not limited.Examples of the ID of the content source may be as follows.

First, a global program ID may be a global identifier for identifyingeach broadcast program. This ID may be directly created by a contentprovider or may be created in the format specified by an authoritativebody. Examples of the ID may include TMSId of “TMS metadata” of NorthAmerica, an EIDR ID which is a movie/broadcast program identifier, etc.

A global channel ID may be a channel identifier for identifying allchannels. Channel numbers differ between MVPDs provided by a set topbox. In addition, even in the same MVPD, channel numbers may differaccording to services designated by users. The global channel ID may beused as a global identifier which is not influenced by an MVPD, etc.According to embodiments, a channel transmitted via a terrestrial wavemay be identified by a major channel number and a minor channel number.If only a program ID is used, since a problem may occur when severalbroadcast stations broadcast the same program, the global channel ID maybe used to specify a specific broadcast channel.

Examples of the ID of the content source to be inserted into a WM mayinclude a program ID and a channel ID. One or both of the program ID andthe channel ID or a new ID obtained by combining the two IDs may beinserted into the WM. According to embodiments, each ID or combined IDmay be hashed to reduce the amount of data. The ID of each contentsource may be of a string type or an integer type. In the case of theinteger type, the amount of transmitted data may be further reduced.

In addition, data which can be delivered via the watermarking schemeaccording to one embodiment of the present invention may include atimestamp. The receiver should know a point of time of currently viewedcontent. This time related information may be referred to as a timestampand may be inserted into the WM. The time related information may takethe form of an absolute time (UTC, GPS, etc.) or a media time. The timerelated information may be delivered up to a unit of milliseconds foraccuracy and may be delivered up to a smaller unit according toembodiments. The timestamp may have a variable length according to typeinformation of the timestamp.

Data which can be delivered via the watermarking scheme according to oneembodiment may include the URL of the interactive application. If aninteractive application related to a currently viewed broadcast programis present, the URL of the application may be inserted into the WM. Thereceiver may detect the WM, obtain the URL, and execute the applicationvia a browser.

FIG. 45 is a diagram showing the meanings of the values of the timestamptype field according to one embodiment of the present invention.

The present invention proposes a timestamp type field as one of datawhich can be delivered via a watermarking scheme. In addition, thepresent invention proposes an efficient data structure of a timestamptype field.

The timestamp type field may be allocated 5 bits. The first two bits ofthe timestamp may mean the size of the timestamp and the next 3 bits maymean the unit of time information indicated by the timestamp. Here, thefirst two bits may be referred to as a timestamp size field and the next3 bits may be referred to as a timestamp unit field.

As shown, according to the size of the timestamp and the unit value ofthe timestamp, a variable amount of real timestamp information may beinserted into the WM. Using such variability, a designer may select asize allocated to the timestamp and the unit thereof according to theaccuracy of the timestamp. If accuracy of the timestamp increases, it ispossible to provide an interactive service at an accurate time. However,system complexity increases as accuracy of the timestamp increases. Inconsideration of this tradeoff, the size allocated to the timestamp andthe unit thereof may be selected.

If the first two bits of the timestamp type field are 00, the timestampmay have a size of 1 byte. If the first two bits of the timestamp typefield are 01, 10 and 11, the size of the timestamp may be 2, 4 and 8bytes, respectively.

If the last three bits of the timestamp type field are 000, thetimestamp may have a unit of milliseconds. If the last three bits of thetimestamp type field are 001, 010 and 011, the timestamp may havesecond, minute and hour units, respectively. The last three bits of thetimestamp type field of 101 to 111 may be reserved for future use.

Here, if the last three bits of the timestamp type field are 100, aseparate time code may be used as a unit instead of a specific time unitsuch as millisecond or second. For example, a time code may be insertedinto the WM in the form of HH:MM:SS:FF which is a time code form ofSMPTE. Here, HH may be an hour unit, MM may be a minute unit and SS maybe a second unit. FF may be frame information. Frame information whichis not a time unit may be simultaneously delivered to provide aframe-accurate service. A real timestamp may have a form of HHMMSSFFexcluding colon in order to be inserted into the WM. In this case, atimestamp size value may have 11 (8 bytes) and a timestamp unit valuemay be 100. In the case of a variable unit, how the timestamp isinserted is not limited by the present invention.

For example, if timestamp type information has a value of 10 andtimestamp unit information has a value of 000, the size of the timestampmay be 4 bits and the unit of the timestamp may be milliseconds. At thistime, if the timestamp is Ts=3265087, 3 digits 087 located at the backof the timestamp may mean a unit of milliseconds and the remainingdigits 3265 may mean a second unit. Accordingly, when this timestamp isinterpreted, a current time may mean that 54 minutes 25.087 seconds haselapsed after the program, into which the WM is inserted, starts. Thisis only exemplary and the timestamp serves as a wall time and mayindicate a time of a receiver or a segment regardless of content.

FIG. 46 is a diagram showing meanings of values of a URL protocol typefield according to one embodiment of the present invention.

The present invention proposes a URL protocol type field as one of datawhich can be delivered via a watermarking scheme. In addition, thepresent invention proposes an efficient data structure of a URL protocoltype field.

Among the above-described information, the length of the URL isgenerally long such that the amount of data to be inserted is relativelylarge. As described above, as the amount of data to be inserted into theWM decreases, efficiency increases. Thus, a fixed portion of the URL maybe processed by the receiver. Accordingly, the present inventionproposes a URL protocol type field.

The URL protocol type field may have a size of 3 bits. A serviceprovider may set a URL protocol in a WM using the URL protocol typefield. In this case, the URL of the interactive application may beinserted starting from a domain and may be transmitted to the WM.

A WM detector of the receiver may first parse the URL protocol typefield, obtain URL protocol information and prefix the protocol to theURL value transmitted thereafter, thereby generating an entire URL. Thereceiver may access the completed URL via a browser and execute theinteractive application.

Here, if the value of the URL protocol type field is 000, the URLprotocol may be directly specified and inserted into the URL field ofthe WM. If the value of the URL protocol type field is 001, 010 and 011,the URL protocols may be http://, https:// and ws://, respectively. TheURL protocol type field values of 100 to 111 may be reserved for futureuse.

The application URL may enable execution of the application via thebrowser (in the form of a web application). In addition, according toembodiments, a content source ID and timestamp information should bereferred to. In the latter case, in order to deliver the content sourceID information and the timestamp information to a remote server, a finalURL may be expressed in the following form.

Request URL: http://domain/path?cid=1233456&t=5005.

In this embodiment, a content source ID may be 123456 and a timestampmay be 5005. CID may mean a query identifier of a content source ID tobe reported to the remote server. t may mean a query identifier of acurrent time to be reported to the remote server.

FIG. 47 is a flowchart illustrating a process of processing a URLprotocol type field according to one embodiment of the presentinvention.

First, a service provider 47010 may deliver content to a WM inserter47020 (s47010). Here, the service provider 47010 may perform a functionsimilar to the above-described content provision server. The WM inserter47020 may insert the delivered content into a WM (s47020). Here, the WMinserter 47020 may perform a function similar to the above-describedwatermark server. The WM inserter 47020 may insert the above-describedWM into audio or video by a WM algorithm. Here, the inserted WM mayinclude the above-described application URL information, content sourceID information, etc. For example, the inserted WM may include theabove-described timestamp type field, the timestamp, the content ID,etc. The above-described protocol type field may have a value of 001 andURL information may have a value of atsc.org. The values of the fieldinserted into the WM are only exemplary and the present invention is notlimited to this embodiment.

The WM inserter 47020 may transmit content, into which the WM isinserted (s47030). Transmission of the content, into which the WM isinserted, may be performed by the service provider 47010.

An STB 47030 may receive the content, into which the WM is inserted, andoutput incompressible A/V data (or raw A/V data) (s47040). Here, the STB47030 may mean the above-described broadcast reception apparatus or theset top box. The STB 47030 may be mounted inside or outside thereceiver.

A WM detector 47040 may detect the inserted WM from the receivedincompressible A/V data (s47050). The WM detector 47040 may detect theWM inserted by the WM inserter 47020 and deliver the detected WM to a WMmanager.

The WM manager 47050 may parse the detected WM (s47060). In theabove-described embodiment, the WM may have a URL protocol type fieldvalue of 001 and a URL value of atsc.org. Since the URL protocol typefield value is 001, this may mean that http://protocol is used. The WMmanager 47050 may combine http:// and atsc.org using this information togenerate an entire URL (s47070).

The WM manager 47050 may send the completed URL to a browser 47060 andlaunch an application (s47080). In some cases, if the content source IDinformation and the timestamp information should also be delivered, theapplication may be launched in the form ofhttp://atsc.org?cid=xxx&t=YYY.

The WM detector 47040 and the WM manager 47050 of the terminal arecombined to perform the functions thereof in one module. In this case,steps s45050, s47060 and s47070 may be processed in one module.

FIG. 48 is a diagram showing the meanings of the values of an eventfield according to one embodiment of the present invention.

The present invention proposes an event field as one of the data whichcan be delivered via the watermarking scheme. In addition, the presentinvention proposes an efficient data structure of an event field.

The application may be launched via the URL extracted from the WM. Theapplication may be controlled via a more detailed event. Events whichcan control the application may be indicated and delivered by the eventfield. That is, if an interactive application related to a currentlyviewed broadcast program is present, the URL of the application may betransmitted and the application may be controlled using events.

The event field may have a size of 3 bits. If the value of the eventfield is 000, this may indicate a “Prepare” command. Prepare is apreparation step before executing the application. A receiver, which hasreceived this command, may download content items related to theapplication in advance. In addition, the receiver may release necessaryresources in order to execute the application. Here, releasing thenecessary resources may mean that a memory is cleaned or otherunfinished applications are finished.

If the event field value is 001, this may indicate an “Execute” command.Execute may be a command for executing the application. If the eventfield value is 010, this may indicate a “Suspend” command. Suspend maymean that the executed application is suspended. If the event fieldvalue is 011, this may indicate a “Kill” command. Kill may be a commandfor finishing the already executed application. The event field valuesof 100 to 111 may be reserved for future use.

FIG. 49 is a diagram showing the meanings of the values of a destinationtype field according to one embodiment of the present invention.

The present invention proposes a destination type field as one of datawhich can be delivered via a watermarking scheme. In addition, thepresent invention proposes an efficient data structure of a destinationtype field.

With development of DTV related technology, supplementary servicesrelated to broadcast content may be provided by a companion device aswell as a screen of a TV receiver. However, companion devices may notreceive broadcast programs or may receive broadcast programs but may notdetect a WM. Accordingly, among applications for providing asupplementary service related to currently broadcast content, if anapplication to be executed by a companion device is present, relatedinformation thereof should be delivered to the companion device.

At this time, even in an environment in which the receiver and thecompanion device interwork, it is necessary to know by which device anapplication or data detected from a WM is consumed. That is, informationabout whether the application or data is consumed by the receiver or thecompanion device may be necessary. In order to deliver such informationas the WM, the present invention proposes a destination type field.

The destination type field may have a size of 3 bits. If the value ofthe destination type field is 0x00, this may indicate that theapplication or data detected by the WM is targeted at all devices. Ifthe value of the destination type field is 0x01, this may indicate thatthe application or data detected by the WM is targeted at a TV receiver.If the value of the destination type field is 0x02, this may indicatethat the application or data detected by the WM is targeted at asmartphone. If the value of the destination type field is 0x03, this mayindicate that the application or data detected by the WM is targeted ata tablet. If the value of the destination type field is 0x04, this mayindicate that the application or data detected by the WM is targeted ata personal computer. If the value of the destination type field is 0x05,this may indicate that the application or data detected by the WM istargeted at a remote server. Destination type field values of 0x06 to0xFF may be reserved for future use.

Here, the remote server may mean a server having all supplementaryinformation related to a broadcast program. This remote server may belocated outside the terminal. If the remote server is used, the URLinserted into the WM may not indicate the URL of a specific applicationbut may indicate the URL of the remote server. The receiver maycommunicate with the remote server via the URL of the remote server andreceive supplementary information related to the broadcast program. Atthis time, the received supplementary information may be a variety ofinformation such as a genre, actor information, synopsis, etc., of acurrently broadcast program as well as the URL of an application relatedthereto. The received information may differ according to system.

According to another embodiment, each bit of the destination type fieldmay be allocated to each device to indicate the destination of theapplication. In this case, several destinations may be simultaneouslydesignated via bitwise OR.

For example, when 0x01 indicates a TV receiver, 0x02 indicates asmartphone, 0x04 indicates a tablet, 0x08 indicates a PC and 0x10indicates a remote server, if the destination type field has a value of0x6, the application or data may be targeted at the smartphone and thetablet.

According to the value of the destination type field of the WM parsed bythe above-described WM manager, the WM manager may deliver eachapplication or data to the companion device. In this case, the WMmanager is a module for processing interworking with the companiondevice in the receiver and may deliver information related to eachapplication or data.

FIG. 50 is a diagram showing the structure of data to be inserted into aWM according to embodiment #1 of the present invention.

In the present embodiment, data inserted into the WM may haveinformation such as a timestamp type field, a timestamp, a content ID,an event field, a destination type field, a URL protocol type field anda URL. Here, the order of data may be changed and each datum may beomitted according to embodiments.

In the present embodiment, a timestamp size field of the timestamp typefield may have a value of 01 and a timestamp unit field may have a valueof 000. This may mean that 2 bits are allocated to the timestamp and thetimestamp has a unit if milliseconds.

In addition, the event field has a value of 001, which means theapplication should be immediately executed. The destination type fieldhas a value of 0x02, which may mean that data delivered by the WM shouldbe delivered to the smartphone. Since the URL protocol type field has avalue of 001 and the URL has a value of atsc.org, this may mean that thesupplementary information or the URL of the application ishttp://atsc.org.

FIG. 51 is a flowchart illustrating a process of processing a datastructure to be inserted into a WM according to embodiment #1 of thepresent invention.

Step s51010 of, at the service provider, delivering content to the WMinserter, step s51020 of, at the WM inserter, inserting the receivedcontent into the WM, step s51030 of, at the WM inserter, transmittingthe content, into which the WM is inserted, step s51040 of, at the STB,receiving the content, into which the WM is inserted, and outputting theincompressible A/V data, step s51050 of, at the WM detector, detectingthe WM, step s51060, at the WM manager, parsing the detected WM and/orstep s51070 of, at the WM manager, generating an entire URL may be equalto the above-described steps.

The WM manager is a companion device protocol module in the receiveraccording to the destination type field of the parsed WM and may deliverrelated data (s51080). The companion device protocol module may manageinterworking and communication with the companion device in thereceiver. The companion device protocol module may be paired with thecompanion device. According to embodiments, the companion deviceprotocol module may be a UPnP device. According to embodiments, thecompanion device protocol module may be located outside the terminal.

The companion device protocol module may deliver the related data to thecompanion device according to the destination type field (s51090). Inembodiment #1, the value of the destination type field is 0x02 and thedata inserted into the WM may be data for a smartphone. Accordingly, thecompanion device protocol module may send the parsed data to thesmartphone. That is, in this embodiment, the companion device may be asmartphone.

According to embodiments, the WM manager or the device protocol modulemay perform a data processing procedure before delivering data to thecompanion device. The companion device may have portability but insteadmay have relatively inferior processing/computing capabilities and asmall amount of memory. Accordingly, the receiver may process datainstead of the companion device and deliver the processed data to thecompanion device.

Such processing may be implemented as various embodiments. First, the WMmanager or the companion device protocol module may select only datarequired by the companion device. In addition, according to embodiments,if the event field includes information indicating that the applicationis finished, the application related information may not be delivered.In addition, if data is divided and transmitted via several WMs, thedata may be stored and combined and then final information may bedelivered to the companion device.

The receiver may perform synchronization using the timestamp instead ofthe companion device and deliver a command related to the synchronizedapplication or deliver an already synchronized interactive service tothe companion device and the companion device may perform display only.Timestamp related information may not be delivered, a time base may bemaintained in the receiver only and related information may be deliveredto the companion device when a certain event is activated. In this case,the companion device may activate the event according to the time whenthe related information is received, without maintaining the time base.

Similarly to the above description, the WM detector and the WM managerof the terminal may be combined to perform the functions thereof in onemodule. In this case, steps s51050, s51060, s51070 and s51080 may beperformed in one module.

In addition, according to embodiments, the companion device may alsohave the WM detector. When each companion device receives a broadcastprogram, into which a WM is inserted, each companion device may directlydetect the WM and then deliver the WM to another companion device. Forexample, a smartphone may detect and parse a WM and deliver relatedinformation to a TV. In this case, the destination type field may have avalue of 0x01.

FIG. 52 is a diagram showing the structure of data to be inserted into aWM according to embodiment #2 of the present invention.

In the present embodiment, data inserted into the WM may haveinformation such as a timestamp type field, a timestamp, a content ID,an event field, a destination type field, a URL protocol type field anda URL. Here, the order of data may be changed and each datum may beomitted according to embodiments.

In the present embodiment, a timestamp size field of the timestamp typefield may have a value of 01 and a timestamp unit field may have a valueof 000. This may mean that 2 bits are allocated to the timestamp and thetimestamp has a unit of milliseconds. The content ID may have a value of123456.

In addition, the event field has a value of 001, which means theapplication should be immediately executed. The destination type fieldhas a value of 0x05, which may mean that data delivered by the WM shouldbe delivered to the remote server. Since the URL protocol type field hasa value of 001 and the URL has a value of remoteserver.com, this maymean that the supplementary information or the URL of the application ishttp://remoteserver.com.

As described above, if the remote server is used, supplementaryinformation of the broadcast program may be received from the remoteserver. At this time, the content ID and the timestamp may be insertedinto the URL of the remote server as parameters and requested from theremote server. According to embodiments, the remote server may obtaininformation about a currently broadcast program via support of API. Atthis time, the API may enable the remote server to acquire the contentID and the timestamp stored in the receiver or to deliver relatedsupplementary information.

In the present embodiment, if the content ID and the timestamp areinserted into the URL of the remote server as parameters, the entire URLmay be http://remoteserver.com?cid=1233456&t=5005. Here, CID may mean aquery identifier of a content source ID to be reported to the remoteserver. Here, t may mean a query identifier of a current time to bereported to the remote server.

FIG. 53 is a flowchart illustrating a process of processing a datastructure to be inserted into a WM according to embodiment #2 of thepresent invention.

Step s53010 of, at the service provider, delivering content to the WMinserter, step s53020 of, at the WM inserter, inserting the receivedcontent into the WM, step s53030 of, at the WM inserter, transmittingthe content, into which the WM is inserted, step s53040 of, at the STB,receiving the content, into which the WM is inserted, and outputting theincompressible A/V data, step s53050 of, at the WM detector, detectingthe WM, and step s53060, at the WM manager, parsing the detected WM maybe equal to the above-described steps.

The WM manager may communicate with the remote server via the parseddestination type field 0x05. The WM manager may generate a URLhttp://remoteserver.com using the URL protocol type field value and theURL value. In addition, a URL http://remoteserver.com?cid=123456&t=5005may be finally generated using the content ID and the timestamp value.The WM manager may make a request using the final URL (s53070).

The remote server may receive the request and transmit the URL of therelated application suitable for the broadcast program to the WM manager(s53080). The WM manager may send the received URL of the application tothe browser and launch the application (s53090).

Similarly to the above description, the WM detector and the WM managerof the terminal may be combined to perform the functions thereof in onemodule. In this case, steps s53050, s53060, s53070 and s53090 may beperformed in one module.

FIG. 54 is a diagram showing the structure of data to be inserted into aWM according to embodiment #3 of the present invention.

The present invention proposes a delivery type field as one of datawhich can be delivered via a watermarking scheme. In addition, thepresent invention proposes an efficient data structure of a deliverytype field.

In order to reduce deterioration in quality of audio/video content dueto increase in amount of data inserted into the WM, the WM may bedivided and inserted. In order to indicate whether the WM is divided andinserted, a delivery type field may be used. Via the delivery typefield, it may be determined whether one WM or several WMs are detectedin order to acquire broadcast related information.

If the delivery type field has a value of 0, this may mean that all datais inserted into one WM and transmitted. If the delivery type field hasa value of 1, this may mean that data is divided and inserted intoseveral WMs and transmitted.

In the present embodiment, the value of the delivery type field is 0. Inthis case, the data structure of the WM may be configured in the form ofattaching the delivery type field to the above-described data structure.Although the delivery type field is located at a foremost part in thepresent invention, the delivery type field may be located elsewhere.

The WM manager or the WM detector may parse the WM by referring to thelength of the WM if the delivery type field has a value of 0. At thistime, the length of the WM may be computed in consideration of thenumber of bits of a predetermined field. For example, as describedabove, the length of the event field may be 3 bits. The size of thecontent ID and the URL may be changed but the number of bits may berestricted according to embodiments.

FIG. 55 is a diagram showing the structure of data to be inserted into aWM according to embodiment #4 of the present invention.

In the present embodiment, the value of the delivery type field maybe 1. In this case, several fields may be added to the data structure ofthe WM.

A WMId field serves as an identifier for identifying a WM. If data isdivided into several WMs and transmitted, the WM detector needs toidentify each WM having divided data. At this time, the WMs each havingthe divided data may have the same WMId field value. The WMId field mayhave a size of 8 bits.

A block number field may indicate an identification number of a currentWM among the WMs each having divided data. The values of the WMs eachhaving divided data may increase by 1 according to order of transmissionthereof. For example, in the case of a first WM among the WMs eachhaving divided data, the value of the block number field may be 0x00. Asecond WM, a third WM and subsequent WMs thereof may have values of0x01, 0x02, . . . . The block number field may have a size of 8 bits.

A last block number field may indicate an identification number of alast WM among WMs each having divided data. The WM detector or the WMmanager may collect and parse the detected WMs until the value of theabove-described block number field becomes equal to that of the lastblock number field. The last block number field may have a size of 8bits.

A block length field may indicate a total length of the WM. Here, the WMmeans one of the WMs each having divided data. The block length fieldmay have a size of 7 bits.

A content ID flag field may indicate whether a content ID is included inpayload of a current WM among WMs each having divided data. If thecontent ID is included, the content ID flag field may be set to 1 and,otherwise, may be set to 0. The content ID flag field may have a size of1 bit.

An event flag field may indicate whether an event field is included inpayload of a current WM among WMs each having divided data. If the eventfield is included, the event flag field may be set to 1 and, otherwise,may be set to 0. The event flag field may have a size of 1 bit.

A destination flag field may indicate whether a destination type fieldis included in payload of a current WM among WMs each having divideddata. If the destination type field is included, the destination flagfield may be set to 1 and, otherwise, may be set to 0. The destinationflag field may have a size of 1 bit.

A URL protocol flag field may indicate whether a URL protocol type fieldis included in payload of a current WM among WMs each having divideddata. If the URL protocol type field is included, the URL protocol flagfield may be set to 1 and, otherwise, may be set to 0. The URL protocolflag field may have a size of 1 bit.

A URL flag field may indicate whether URL information is included inpayload of a current WM among WMs each having divided data. If the URLinformation is included, the URL flag field may be set to 1 and,otherwise, may be set to 0. The URL flag field may have a size of 1 bit.

The payload may include real data in addition to the above-describedfields.

If data is divided into several WMs and transmitted, it is necessary toknow information about when each WM is inserted. In this case, accordingto embodiments, a timestamp may be inserted into each WM. At this time,a timestamp type field may also be inserted into the WM, into which thetimestamp is inserted, in order to know when the WM is inserted.Alternatively, according to embodiments, the receiver may store and useWM timestamp type information. The receiver may perform timesynchronization based on a first timestamp, a last timestamp or eachtimestamp.

If data is divided into several WMs and transmitted, the size of each WMmay be adjusted using the flag fields. As described above, if the amountof data transmitted by the WM increases, the quality of audio/videocontent may be influenced. Accordingly, the size of the WM inserted intoa frame may be adjusted according to the transmitted audio/video frame.At this time, the size of the WM may be adjusted by the above-describedflag fields.

For example, assume that any one of video frames of content has a blackscreen only. If a scene is switched according to content, one videoframe having a black screen only may be inserted. In this video frame,the quality of content may not deteriorate even when a large amount ofWMs is inserted. That is, a user does not sense deterioration in contentquality. In this case, A WM having a large amount of data may beinserted into this video frame. At this time, most of the values of theflag fields of the WM inserted into the video frame may be 1. This isbecause the WM have most of the fields. In particular, a URL fieldhaving a large amount of data may be included in that WM. Therefore, arelatively small amount of data may be inserted into other video frames.The amount of data inserted into the WM may be changed according todesigner's intention.

FIG. 56 is a diagram showing the structure of data to be inserted into afirst WM according to embodiment #4 of the present invention.

In the present embodiment, if the value of the delivery type field is 1,that is, if data is divided into several WMs and transmitted, thestructure of a first WM may be equal to that shown in FIG. 56.

Among WMs each having divided data, a first WM may have a block numberfield value of 0x00. According to embodiments, if the value of the blocknumber field is differently used, the shown WM may not be a first WM.

The receiver may detect the first WM. The detected WM may be parsed bythe WM manager. At this time, it can be seen that the delivery typefield value of the WM is 1 and the value of the block number field isdifferent from that of the last block number field. Accordingly, the WMmanager may store the parsed information until the remaining WM having aWMID of 0x00 is received. In particular, atsc.org which is URLinformation may also be stored. Since the value of the last block numberfield is 0x01, when one WM is further received in the future, all WMshaving a WMID of 0x00 may be received.

In the present embodiment, all the values of the flag fields are 1.Accordingly, it can be seen that information such as the event field isincluded in the payload of this WM. In addition, since the timestampvalue is 5005, a time corresponding to a part, into which this WM isinserted, may be 5.005 seconds.

FIG. 57 is a diagram showing the structure of data to be inserted into asecond WM according to embodiment #4 of the present invention.

In the present embodiment, if the value of the delivery type field is 1,that is, if data is divided into several WMs and transmitted, thestructure of a second WM may be equal to that shown in FIG. 57.

Among WMs each having divided data, a second WM may have a block numberfield value of 0x01. According to embodiments, if the value of the blocknumber field is differently used, the shown WM may not be a second WM.

The receiver may detect the second WM. The WM manager may parse thedetected second WM. At this time, since the value of the block numberfield is equal to that of the last block number field, it can be seenthat this WM is a last WM of the WMs having a WMId value of 0x00.

Among the flag fields, since only the value of the URL flag is 1, it canbe seen that URL information is included. Since the value of the blocknumber field is 0x01, this information may be combined with alreadystored information. In particular, the already stored atsc.org part andthe /apps/app1.html part included in the second WM may be combined. Inaddition, in the already stored information, since the value of the URLprotocol type field is 001, the finally combined URL may behttp://atsc.org/apps/app1.html. This URL may be launched via thisbrowser.

According to the second WM, a time corresponding to a part, into whichthe second WM is inserted, may be 10.005 seconds. The receiver mayperform time synchronization based on 5.005 seconds of the first WM ormay perform time synchronization based on 10.005 seconds of the last WM.In the present embodiment, the WMs are transmitted twice at an intervalof 5 seconds. Since only audio/video may be transmitted during 5 secondsfor which the WM is not delivered, deterioration in quality of contentmay be prevented. That is, even when data is divided into several WMsand transmitted, quality deterioration may be reduced. A time when theWM is divided and inserted may be changed according to embodiments.

FIG. 58 is a flowchart illustrating a process of processing thestructure of data to be inserted into a WM according to embodiment #4 ofthe present invention.

Step s58010 of, at the service provider, delivering content to the WMinserter, step s58020 of, at the WM inserter, inserting the receivedcontent into the WM #1, step s58030 of, at the WM inserter, transmittingthe content, into which the WM #1 is inserted, step s58040 of, at theSTB, receiving the content, into which the WM #1 is inserted, andoutputting the incompressible A/V data, and step s58050 of, at the WMdetector, detecting the WM #1 may be equal to the above-described steps.

WM #1 means one of WMs into which divided data is inserted and may be afirst WM in embodiment #4 of the present invention. As described above,the block number field of this WM is 0x00 and URL information may beatsc.org.

The WM manager may parse and store detected WM #1 (s58060). At thistime, the WM manager may perform parsing by referring to the number ofbits of each field and the total length of the WM. Since the value ofthe block number field is different from the value of the last blocknumber field and the value of the delivery type field is 1, the WMmanager may parse and store the WM and then wait for a next WM.

Here, step s58070 of, at the service provider, delivering the content tothe WM inserter, step s58080 of, at the WM inserter, inserting thereceived content to WM #2, step s58090 of, at the WM inserter,transmitting the content, into which WM #2 is inserted, step s58100 of,at the STB, receiving the content, into which WM #2 is inserted, andoutputting incompressible A/V data and/or step s58110 of, at the WMdetector, detecting WM #2 may be equal to the above-described steps.

WM #2 means one of WMs into which divided data is inserted and may be asecond WM in embodiment #4 of the present invention. As described above,the block number field of this WM is 0x01 and URL information may be/apps/app1.html.

The WM manager may parse and store detected WM #2 (s58120). Theinformation obtained by parsing WM #2 and the information obtained byparsing already stored WM #1 may be combined to generate an entire URL(s58130). In this case, the entire URL may behttp://atsc.org/apps/app1.html as described above.

Step s58140 of, at the WM manager, delivering related data to thecompanion device protocol module of the receiver according to thedestination type field and step s58150 of, at the companion deviceprotocol module, delivering related data to the companion deviceaccording to the destination type field may be equal to theabove-described steps.

The destination type field may be delivered by WM #1 as described above.This is because the destination flag field value of the first WM ofembodiment #4 of the present invention is 1. As described above, thisdestination type field value may be parsed and stored. Since thedestination type field value is 0x02, this may indicate data for asmartphone.

The companion device protocol module may communicate with the companiondevice to process the related information, as described above. Asdescribed above, the WM detector and the WM manager may be combined. Thecombined module may perform the functions of the WM detector and the WMmanager.

FIG. 59 is a diagram showing the structure of a watermark based imagedisplay apparatus according to another embodiment of the presentinvention.

This embodiment is similar to the structure of the above-describedwatermark based image display apparatus, except that a WM manager t59010and a companion device protocol module t59020 are added under awatermark extractor s59030. The remaining modules may be equal to theabove-described modules.

The watermark extractor t59030 may correspond to the above-described WMdetector.

The watermark extractor t59030 may be equal to the module having thesame name as that of the structure of the above-described watermarkbased image display apparatus. The WM manager t59010 may correspond tothe above-described WM manager and the companion device protocol modulet59020 may correspond to the above-described companion device protocolmodule. Operations of the modules have been described above.

FIG. 60 is a diagram showing a data structure according to oneembodiment of the present invention in a fingerprinting scheme.

In the case of a fingerprinting (FP) ACR system, deterioration inquality of audio/video content may be reduced as compared to the case ofusing a WM. In the case of the fingerprinting ACR system, sincesupplementary information is received from an ACR server, qualitydeterioration may be less than that of the WM directly inserted intocontent.

When information is received from the ACR server, since qualitydeterioration is reduced as described above, the data structure used forthe WM may be used without change. That is, the data structure proposedby the present invention may be used even in the FP scheme.Alternatively, according to embodiments, only some of the WM datastructure may be used.

If the above-described data structure of the WM is used, the meaning ofthe destination type field value of 0x05 may be changed. As describedabove, if the value of the destination type field is 0x05, the receiverrequests data from the remote server. In the FP scheme, since thefunction of the remote server is performed by the ACR server, thedestination type field value 0x05 may be deleted or redefined.

The remaining fields may be equal to the above-described fields.

FIG. 61 is a flowchart illustrating a process of processing a datastructure according to one embodiment of the present invention in afingerprinting scheme.

A service provider may extract a fingerprint (FP) from a broadcastprogram to be transmitted (s61010). Here, the service provider may beequal to the above-described service provider. The service provider mayextract the fingerprint per content using a tool provided by an ACRcompany or using a tool thereof. The service provider may extract anaudio/video fingerprint.

The service provider may deliver the extracted fingerprint to an ACRserver (s61020). The fingerprint may be delivered to the ACR serverbefore a broadcast program is transmitted in the case of a pre-producedprogram or as soon as the FP is extracted in real time in the case of alive program. If the FP is extracted in real time and delivered to theACR server, the service provider may assign a content ID to content andassign information such as a transmission type, a destination type or aURL protocol type. The assigned information may be mapped to the FPextracted in real time and delivered to the ACR server.

The ACR server may store the received FP and related information thereofin an ACR DB (s61030). The receiver may extract the FP from anexternally received audio/video signal. Here, the audio/video signal maybe an incompressible signal. This FP may be referred to as a signature.The receiver may send a request to the server using the FP (s61040).

The ACR server may compare the received FP and the ACR DB. If an FPmatching the received FP is present in the ACR DB, the content broadcastby the receiver may be recognized. If the content is recognized,delivery type information, timestamp, content ID, event typeinformation, destination type information, URL protocol typeinformation, URL information, etc. may be sent to the receiver (s61050).

Here, each information may be transmitted in a state of being includedin the above-described field. For example, the destination typeinformation may be transmitted in a state of being included in thedestination type field. When responding to the receiver, the datastructure used in the above-described WM may be used as the structure ofthe delivered data.

The receiver may parse the information received from the ACR server. Inthe present embodiment, since the value of the destination type field is0x01, it can be seen that the application of the URL is executed by theTV. A final URL http://atsc.org may be generated using the value of theURL protocol type field and the URL information. The process ofgenerating the URL may be equal to the above-described process.

The receiver may execute a broadcast related application via a browserusing the URL (s61060). Here, the browser may be equal to theabove-described browser. Steps s61040, s614050 and s61060 may berepeated.

FIG. 62 illustrates a method of providing interactive services accordingto an embodiment of the present invention.

The method includes receiving an uncompressed broadcast content(s62010),extracting the embedded watermark(s62020), parsing the extractedwatermark(s62030), generating an URL(s62040) and/or launching anapplication by using the generated URL(s62050).

The receiver can receive uncompressed broadcast contents from anexternal receiving unit(s62010). The external receiving unit cancorrespond to STB, described above. The uncompressed contents can bedelivered to WM detector, described above. The uncompressed contents caninclude WM. As described above, the watermark can be embedded/insertedin a video/audio frame of the content. There can be plural WMs insertedin each plural frames of the uncompressed contents. The broadcastcontents can be delivered to the receiver in forms of uncompressedcontents, by STB, as described above.

The receiver can extract the embedded WM from the received uncompressedcontent(s62020). The extraction can be conducted by WM manager,described above. Also, the receiver can parse the extracted WM(s62030).The parsing can be conducted by WM manager as well.

The receiver or the WM manager described above, can generate anURL(s62040). The URL is for the application related to the interactiveservice. The application can provide the interactive services related tothe uncompressed broadcast content. With the application, the user canbe provided with the interactive service about the broadcast contents.

The receiver or the WM manager can use URL to launch theapplication(s62050). This step may correspond to the WM managerlaunching App. by using the browser. The browser may correspond to theabove described browser.

In a method of providing interactive services according to otherembodiment of the present invention, the watermark includes an URL fieldincluding a fraction of the URL, an URL protocol field indicating aprotocol that the URL uses. As described above, the URL field caninclude a part of URL, such as “atsc.org”. The URL protocol field,corresponding to the URL protocol field described above, can indicateprotocols, such as http://, https://, etc.

In a method of providing interactive services according to anotherembodiment of the present invention, the receiver can generate finalURL, by using the URL field and the URL protocol field. The generationprocess can be conducted by WM manager. The WM manager can combine theURL part carried by the URL field, and the protocol part of the URLindicated by the URL protocol field. The parts of the URL can bedelivered to the receiver, through plural WMs. That is, the URL can bedivided into even smaller parts, other than the embodiment describedabove. By combining the URL related information, the final URL can begenerated.

In a method of providing interactive services according to anotherembodiment of the present invention, the uncompressed broadcast contentcan include plural WMs. The WMs can be inserted in plural video or audioframes of the broadcast content. The each WMs can include a fraction ofthe data that supposed to be delivered to the receiver. This embodimentmay correspond to the embodiment using plural WMs including dividedinformation, described above. Each of the WMs can include a deliverytype field, described above. The delivery type field can indicate thatthe data is divided into plural fractions, and each fractions of dataare being delivered by using the plural WMs.

In a method of providing interactive services according to anotherembodiment of the present invention, sizes of the each plural watermarksfor the each frames can be adjusted by having a fraction of differentsizes, based on quality of the each frames. As described above, in acase that plural WMs are used for carrying divided data, sizes of theeach WMs can be adjusted. In that case, the size of WM can be adjustedby having certain fields or not. The configuration of the WM, what kindof information is included, can be recognized with flag information. Byadjusting sizes based on quality situation in video/audio frames, thetotal quality of the contents can be prevented from qualitydeterioration.

In a method of providing interactive services according to anotherembodiment of the present invention, the each plural watermarks includeflag information indicating configuration of the fraction of the datainserted in the each plural watermarks. Here, the flag informationcorresponds to such as, URL flag field, URL protocol flag field, and soon.

In a method of providing interactive services according to anotherembodiment of the present invention, in case that plural WMs are usedfor carrying plural fractions of data, one of the watermarks includesthe URL protocol field, and one of the other watermarks includes the URLfield. As described before, the parts of URL can be carried in severalWMs by being carried in URL fields.

In a method of providing interactive services according to anotherembodiment of the present invention, the watermark further includes atimestamp size field, a timestamp unit field, an event field and adestination type field. The timestamp size field indicates number ofbytes allocated for timestamps in the watermark. The timestamp unitfield indicates time unit of the timestamps. The event field includes acommand related to the application. The destination type field indicatesa secondary device that the application is targeting. The timestampsestablish time base for synchronizing the interactive services with theuncompressed broadcast content. Each fields are described above.

In a method of providing interactive services according to anotherembodiment of the present invention, the method further includesdelivering the information in the parsed watermark to the secondarydevice that the application is targeting. As described above, thecompanion device protocol module can deliver information targetingsecond screen device, to corresponding second screen device.

In a method of providing interactive services according to anotherembodiment of the present invention, the receiver can process the ininformation in the parsed watermark, before delivering the informationto the second screen device. Either WM manager or companion deviceprotocol module can process information for second screen devices. Theembodiments of such processing are described above. With suchprocessing, the complexity on companion device's side can be reduced.

The above-described steps can be omitted or replaced by steps executingsimilar or identical functions according to design.

Although the description of the present invention is explained withreference to each of the accompanying drawings for clarity, it ispossible to design new embodiment(s) by merging the embodiments shown inthe accompanying drawings with each other. And, if a recording mediumreadable by a computer, in which programs for executing the embodimentsmentioned in the foregoing description are recorded, is designed innecessity of those skilled in the art, it may belong to the scope of theappended claims and their equivalents.

An apparatus and method according to the present invention may benon-limited by the configurations and methods of the embodimentsmentioned in the foregoing description. And, the embodiments mentionedin the foregoing description can be configured in a manner of beingselectively combined with one another entirely or in part to enablevarious modifications.

In addition, a method according to the present invention can beimplemented with processor-readable codes in a processor-readablerecording medium provided to a network device. The processor-readablemedium may include all kinds of recording devices capable of storingdata readable by a processor. The processor-readable medium may includeone of ROM, RAM, CD-ROM, magnetic tapes, floppy discs, optical datastorage devices, and the like for example and also include such acarrier-wave type implementation as a transmission via Internet.Furthermore, as the processor-readable recording medium is distributedto a computer system connected via network, processor-readable codes canbe saved and executed according to a distributive system.

It will be appreciated by those skilled in the art that variousmodifications and variations can be made in the present inventionwithout departing from the spirit or scope of the inventions. Thus, itis intended that the present invention covers the modifications andvariations of this invention provided they come within the scope of theappended claims and their equivalents.

Both apparatus and method inventions are mentioned in this specificationand descriptions of both of the apparatus and method inventions may becomplementarily applicable to each other.

Various embodiments have been described in the best mode for carryingout the invention.

The present invention is available in a series of broadcast signalprovision fields.

It will be apparent to those skilled in the art that variousmodifications and variations can be made in the present inventionwithout departing from the spirit or scope of the inventions. Thus, itis intended that the present invention covers the modifications andvariations of this invention provided they come within the scope of theappended claims and their equivalents.

What is claimed is:
 1. A method of processing a supplementary content ina digital receiving apparatus, the method comprising: connecting to anexternal device being different from a broadcaster; receiving anuncompressed audio/video (A/V) content from the external device;extracting an audio watermark from the uncompressed A/V content, whereinthe audio watermark includes type information related to a first uniformresource locator (URL), time information and an event flag, further theevent flag is used to signal when an event is available, constructingthe first URL based on the audio watermark; transmitting a request to aremote server based on the first URL; receiving a second URL for thesupplementary content from the remote server; and presenting thesupplementary content based on the second URL.
 2. The method of claim 1,further comprising: processing the supplementary content based on anautomatic content recognition (ACR).
 3. The method of claim 2, whereinthe type information is used to identify a small domain or a largedomain, and the time information is used to identify an interval of theuncompressed A/V content in which the audio watermark is embedded. 4.The method of claim 3, further comprising: extracting a video watermarkfrom the uncompressed A/V content.
 5. The method of claim 4, wherein thevideo watermark includes first URL data and second URL data, and thefirst URL data includes signaling bits which identify a first portion ofa final URL, wherein the second URL data includes a second portion ofthe final URL, and wherein values of the signaling bits are pre-assignedto specific URL strings.
 6. A digital receiving apparatus for processinga supplementary content, the digital receiving apparatus comprising: areceiver configured to connect to an external device being differentfrom a broadcaster, wherein the receiver is further configured toreceive an uncompressed audio/video (A/V) content from the externaldevice; a manager configured to extract an audio watermark from theuncompressed A/V content, wherein the audio watermark includes typeinformation related to a first uniform resource locator (URL), timeinformation and an event flag, further the event flag is used to signalwhen an event is available, wherein the manager is further configuredto: construct the first URL based on the audio watermark, transmit arequest to a remote server based on the first URL, and receive a secondURL for the supplementary content from the remote server; and a displaydevice to present the supplementary content based on the second URL. 7.The digital receiving apparatus of claim 6, wherein the managerprocesses the supplementary content based on an automatic contentrecognition (ACR).
 8. The digital receiving apparatus of claim 7,wherein the type information is used to identify a small domain or alarge domain, and the time information is used to identify an intervalof the uncompressed A/V content in which the audio watermark isembedded.
 9. The digital receiving apparatus of claim 8, wherein themanager is further configured to extract a video watermark from theuncompressed A/V content.
 10. The digital receiving apparatus of claim9, wherein the video watermark includes first URL data and second URLdata, and the first URL data includes signaling bits which identify afirst portion of a final URL, wherein the second URL data includes asecond portion of the final URL, and wherein values of the signalingbits are pre-assigned to specific URL strings.